=========================================================================
Path: yktvmv!jbs
Subject: Re: The Road To Riches (Somewhat Off-Topic)
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,talk.environment,talk.politics.libertarian,talk.politics.misc
Message-ID: <20000105.160145.782@yktvmv.watson.ibm.com>
Date: Wed, 5 Jan 2000 21:01:45 GMT
References: <84qivr$dn7$1@nnrp1.deja.com> <84t5nl$8nd$1@nnrp1.deja.com>
   <38722191.67016894@news.rmi.net> <84u6vg$t87$1@nnrp1.deja.com>
   <84uhgj$7u4$1@nntp8.atl.mindspring.net> <84vscj$3pp$1@nnrp1.deja.com>
 
In article <84vscj$3pp$1@nnrp1.deja.com>,
 on Wed, 05 Jan 2000 16:44:07 GMT,
 Langrrr <Langrrr@aol.com> writes (in part):
>> 	Where does rich people's income come from? Huge plantations of
>> money trees?
>>
>
>It certainly doesn't come in the form of a government welfare check.
 
         Actually many rich people derive substantial income from
government favors obtained by political influence in opposition
to the public interest.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: The Road To Riches (Somewhat Off-Topic)
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,talk.environment,talk.politics.libertarian,talk.politics.misc
Message-ID: <20000106.194546.054@yktvmv.watson.ibm.com>
Date: Fri, 7 Jan 2000 00:45:46 GMT
References: <84qivr$dn7$1@nnrp1.deja.com> <84t5nl$8nd$1@nnrp1.deja.com>
   <38722191.67016894@news.rmi.net> <84u6vg$t87$1@nnrp1.deja.com>
   <84uhgj$7u4$1@nntp8.atl.mindspring.net> <84vscj$3pp$1@nnrp1.deja.com>
   <20000105.160145.782@yktvmv.watson.ibm.com> <852bci$teg$1@nnrp1.deja.com>
 
In article <852bci$teg$1@nnrp1.deja.com>,
 on Thu, 06 Jan 2000 15:12:32 GMT,
 Langrrr <Langrrr@aol.com> writes:
>In article <20000105.160145.782@yktvmv.watson.ibm.com>,
>  jbs@watson.ibm.com wrote:
>> In article <84vscj$3pp$1@nnrp1.deja.com>,
>>  on Wed, 05 Jan 2000 16:44:07 GMT,
>>  Langrrr <Langrrr@aol.com> writes (in part):
>> >> 	Where does rich people's income come from? Huge plantations of
>> >> money trees?
>> >>
>> >
>> >It certainly doesn't come in the form of a government welfare check.
>>
>>          Actually many rich people derive substantial income from
>> government favors obtained by political influence in opposition
>> to the public interest.
>
>That is a misapplication of a subject to the issue at hand.  The rich,
>as was being discussed by Loren Petrich, did not amass their wealth by
>receiving government welfare checks.
 
         Actually some of them did in effect.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Global Warming
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000112.190012.751@yktvmv.watson.ibm.com>
Date: Thu, 13 Jan 2000 00:00:12 GMT
References: <3870AD4F.515CA64@math.nwu.edu>
   <20000109165404.01006.00000704@ng-fa1.aol.com> <387A3AC6.10E847A1@math.nwu.edu>
   <387BA3EF.596A9794@psl.nmsu.edu> <387c535d.0@news.nwl.ac.uk>
 
In article <387c535d.0@news.nwl.ac.uk>,
 on 12 Jan 2000 10:11:41 GMT,
 wmc@bas.ac.uk writes (in part):
>Steve McGee <smcgee@psl.nmsu.edu> wrote:
         <snip>
>>    In a well mixed troposphere what physical phenomenon would
>>    you suggest that allows the surface to warm more than the
>>    layers above?
>
>I'm not sure. But in a well-mixed trop, what phys would *you*
>suggest that allows the layers above to warm more than the sfc...?
 
         This wasn't addressed to me, however how about the fact
that the moist adiabatic lapse rate decreases as temperature
increases?
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: The Road To Riches (Somewhat Off-Topic)
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,talk.environment,talk.politics.libertarian,talk.politics.misc
Message-ID: <20000115.223548.837@yktvmv.watson.ibm.com>
Date: Sun, 16 Jan 2000 03:35:48 GMT
References: <84qivr$dn7$1@nnrp1.deja.com> <x4hvh5bggvp.fsf@Steam.Stanford.EDU>
   <84rsp9$i1u$1@nntp8.atl.mindspring.net> <x4hg0wewh0a.fsf@Steam.Stanford.EDU>
   <84s12e$p$1@nntp1.atl.mindspring.net> <84t5nl$8nd$1@nnrp1.deja.com>
   <38722191.67016894@news.rmi.net> <84u6vg$t87$1@nnrp1.deja.com>
   <3872bf9e.107481923@news.rmi.net> <84vrlt$39r$1
   <85g2t4$i10$1@news.dgsys.com> <85gboo$qlf$1@nnrp1.deja.com>
   <85n159$cot$1@news.dgsys.com> <85necr$vc9$1@nnrp1.deja.com>
   <85nnff$nub$1@news.dgsys.com>
 
In article <85nnff$nub$1@news.dgsys.com>,
 on 14 Jan 2000 17:47:27 GMT,
 jhalpern@ms1.dgsys.com (Joshua Halpern) writes:
>Langrrr (Langrrr@aol.com) wrote:
>: In article <85n159$cot$1@news.dgsys.com>,
>:   jhalpern@ms1.dgsys.com (Joshua Halpern) wrote:
>: > Langrrr (Langrrr@aol.com) wrote:
>: > : In article <85g2t4$i10$1@news.dgsys.com>,
>: > :   jhalpern@ms1.dgsys.com (Joshua Halpern) wrote:
>: > : SNIP...
>:
>: Our system of Federalism places an emphasis on the system of dual
>: sovereigns - for the very reasons outlined by Justice O'Connor in New
>: York v. United States (which I once again urge everyone to read.  It's
>: a 1992 decision available on findlaw.com).  By diffusing power, we
>: create an additional check on that power becoming to concentrated and
>: thus harmful to individual rights.
>:
>Dual sovereigns is an oxymoron.  Can't be done.  One has to
>be primary.
>
>josh halpern
 
         Does this apply to marriages?
 
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Failure to Predict Blizzard Casts Doubt on Global Warming
   Forecasts
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000210.185321.351@yktvmv.watson.ibm.com>
Date: Thu, 10 Feb 2000 23:53:21 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A1C751.1CC95808@math.nwu.edu>
   <jscanlon-65A2ED.18034209022000@news.linex.com> <38A30AA0.51210914@math.nwu.edu>
 
In article <38A30AA0.51210914@math.nwu.edu>,
 on Thu, 10 Feb 2000 12:59:44 -0600,
 Leonard Evens <len@math.nwu.edu> writes:
>Jim Scanlon wrote:
                   <snip>
>> To reinforce Len's comments I watched most of an excellent PBS
>> presentation on Nova of the bail out of Long Term Capital Investment
>> firm which used sophisticated mathematical models to remove the risk
>> from investing very large sums of money in global financial markest.
>> They were quite successful returning 43% the first year (minimum
>> investment $10 million). Returns dwindled to 17% as  more firms
>> expolited the markets. However when the long term pattern of the global
>> financial system was perturbed by unusual crises in Asia and Russia at
>> the same time the model and reality parted and LTCI started losing $500
>> million a day.
>
>>
>> Models are very useful tools, but they all have their limits. My
>> understanding of the use of climate models is that they do not "predict"
>> the future but extend,or project various scenarios to give an
>> intelligent estimate of what lies ahead. It's not exactly like
>> predicting the outcome of an elextion based on early returns of reliable
>> voting information--which is pretty good.
>
>What you say is correct, but I think one should not try to
>draw too many conclusions about models in general from one
>sort of model.   About the only thing the economics models
>used by LTCI and climate models have in common is that they
>use computers to do the numerical calculations since exact
>analytic solutions are not possible.   But they are based
>on entirely different theoretical analyses in unrelated
>subjects, and the numerical difficulties they deal with are
>of entirely different orders of magnitude and arise for
>entirely different reasons.  Projections based on early
>returns are based on statistical models which have even
>less to do with either climate models or those used by
>LTIC.
 
         I don't think this is exactly right.
         First it is my understanding (which may be wrong) that
LTCM (Long-Term Capital Management, I believe this is the intended
name) was not in fact using sophisticated mathematical models but
instead rather simple minded models based on historical price
relationships between various financial instruments.  These
sorts of financial models are somewhat similar to "key precinct"
type electoral models (which are based on historical relationships
between voting results in different precincts).  There are also
some climate models based on historical relationships (ie El Nino
vrs La Nina).  Such models can fail spectacularly if the system
moves outside the often rather limited domain they are based on.
         I also think it is possible to draw general conclusions
from the LTCM fiasco.  One is that it is dangerous to rely on
reputations.  The people involved in LTCM had glittering
reputations.  As a result their investors and creditors failed
to take reasonable precautions which could have averted much of
the trouble.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: LTCM, models and experts
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000211.170840.688@yktvmv.watson.ibm.com>
Date: Fri, 11 Feb 2000 22:08:40 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A1C751.1CC95808@math.nwu.edu>
   <jscanlon-65A2ED.18034209022000@news.linex.com> <38A30AA0.51210914@math.nwu.edu>
   <20000210.185321.351@yktvmv.watson.ibm.com> <38A42D1B.F00BCBCD@math.nwu.edu>
 
In article <38A42D1B.F00BCBCD@math.nwu.edu>,
 on Fri, 11 Feb 2000 09:39:07 -0600,
 Leonard Evens <len@math.nwu.edu> writes:
>jbs@watson.ibm.com wrote:
 
         <snip>
 
>>          I don't think this is exactly right.
>>          First it is my understanding (which may be wrong) that
>> LTCM (Long-Term Capital Management, I believe this is the intended
>> name) was not in fact using sophisticated mathematical models but
>> instead rather simple minded models based on historical price
>> relationships between various financial instruments.
>
>I am not a financial model expert, so be warned that what I
>say may be misleading.   And of course, I was not a partner
>or employee of LTCM, so I don't know what they were actually
>doing.   But it is my impression---confirmed by a recent
>NOVA presentation---that LTCM used variations of the
>Black Scholes model.   Although the mathematics of this model
>are relatively simple compared to many models used in physical
>science, it does involve theoretical principles which supposedly
>apply to options trading.   I don't believe it is basically
>an extrapolation based on historical trends.   There are of
>course assumptions built into the model, which if they fail
>to apply, then the results may be nonsense.   I've read a bit
>about LTCM and also seen the NOVA presentation, and right now
>I'm a bit confused about what is supposed to have gone wrong.
>It was my impression that it was not a failure of the model
>per se but how LTCM tried to apply it in a real situation.
 
         Of course LTCM used Black Scholes and variants.  These
models have well known limitations which did not so far as I
know have anything much to do with what went wrong.  What went
wrong was LTCM (like many before them and no doubt many after
them) was excessively leveraged.
         It is my understanding that a typical LTCM position
was similar to the following.  Suppose we, LTCM, notice
that the government has a bond outstanding which will be
redeemed in 5 years at par ($1000 per bond) and meanwhile
pays 9%.  Call this the red bond.  Suppose there is another bond,
the blue bond, which is absolutely identical except that for
some reason the red bond is currently selling at $900 while the
blue bond costs $1000.  This looks like a price anomaly which
can exploited.  How do we do this.  Suppose we start with $9000.
We buy 10 red bonds.  We take our bonds to the bank and request a
loan offering the bonds as collateral.  Since we are LTCM and
really hot stuff the bank allows us to borrow 100% of our
collateral at 5.5% interest.  This loan is open indefinitely but
we must keep it 100% collateralized.  This is figured on a daily
basis.  We take the $9000 from the bank and buy TBills paying 5%
interest.  We find someone, X, holding blue bonds and planning
to hold them to maturity.  We ask to borrow 9 blue bonds from
X and offer the TBills as collateral.  As a sweetener we offer
.5% additional interest per year.  Naturally we agree to keep
the loan 100% collateralized (on a daily basis) and we get the
TBill interest and X gets the bond interest.  X agrees as it
appears a safe way to get an additional .5% yield.  We now take
the 9 blue bonds and sell them on the open market.  This gets
us our $9000 back.  Now every year we owe $495 interest to the
bank and $855 to X ($810 from the borrowed 9% bonds and $45 for
the extra .5%) a total of $1350.  But we receive $450 interest
on the TBills and $900 interest on the red bonds (the bank is
holding them but we still get the interest).  This also totals
$1350 so our carrying cost is zero (I picked the numbers to
make it come out this way).  But in 5 years when the bonds
come due and we unwind everything we end up $1000 ahead because
our 10 red bonds are now worth $10000 while the 9 blue bonds
which we borrowed are only worth $9000.
         So we have increased the return on our $9000 capital
by $1000 over 5 years or about 2% a year.  Of course 2% a year
does not sound all that impressive.  However that is no problem,
we at LTCM are real men not a bunch of wimps.  We take our $9000
and do the above deal again and again.  In fact we do it 20 times.
This increases our excess return to 40% a year (simple interest)
which sounds a lot better.  Now if we did this 20 times with the
same bank they might figure out what we were doing.  This would
make them nervous.  No problem, we deal with 10 different banks.
Now banks ask ordinary borrowers tedious questions like what
other loans they have outstanding.  But fortunately we are LTCM
and it would be very gauche for some lowly loan officer to ask
us a question like that.
         The above may be incorrect in detail but I believe it
captures the essential elements of the LTCM trading strategy.
Now you may ask where is the sophisticated mathematical model.
Good question.  I believe the answer is "there wasn't one".
Now this is not entirely fair as in the real world it is rare
for the red and blue bonds to be absolutely identical but
differently priced.  Instead you find similar but not absolutely
identical bonds and apply the same strategy.  In doing this you
may create synthetic securities (consisting for example of .5
of a 4 year bond and .5 of a 6 year bond) to get sufficiently
similarly behaving pairs.  This can involve elaborate models.
However it does nothing to eliminate the risk present even in
the simple case with identical bonds and it is this risk which
I believe did LTCM in.
         What is this risk, what could possibly go wrong?  Very
simple.  While it is true that in 5 years the red bond will be
worth $1000 and so one would expect the price to gradually rise
from the current $900 to $1000 over the 5 year period, this does
not mean the price cannot fall temporarily.  Suppose the red bond
price falls to $890.  Now the collateral for your $9000 loan from
bank is worth $8900 and they want $100 like right now.  Well no
problem you have $9000 capital.  But wait, real men that you were,
you did the deal 20 times.  So you must part with $2000 over 20%
of your capital.  Ouch.  But there's worse to come.  Rumors start
going around Wall Street that LTCM is in trouble and may have to
unwind its positions.  Furthermore somehow Wall Street has
figured out you own a gazillion red bonds which you would have
sell and have shorted a gazillion blue bonds which you would have
to buy back.  So what happens, the red bond price falls a bit
more to $880 in case you are about to dump a bunch of red bonds
on the market and the blue bond price rises a bit to $1010 in case
there is about to be a shortage of blue bonds.  So now your not
quite so friendly banks want another $2000 and furthermore X wants
another $1800 TBills collateral.  Ouch.  Ouch.
         Well you get the picture.
 
>> These
>> sorts of financial models are somewhat similar to "key precinct"
>> type electoral models (which are based on historical relationships
>> between voting results in different precincts).  There are also
>> some climate models based on historical relationships (ie El Nino
>> vrs La Nina).  Such models can fail spectacularly if the system
>> moves outside the often rather limited domain they are based on.
>
>I am not a climatologist, so be warned that what I now say may
>be misleading because of my lack of understanding.
>
>I think when people talk about "climate models", they generally
>are referring the GCMs (general circulation models).   These
>use well established principles in thermodynamics
>and fluid mechanics to model the Earth's atmosphere and/or
>ocean either separately or in some sort of combination.
>Unfortunately, it is necessary to make major approximations
>to get the programs to run on computers.  For example,
>an awful lot of information has to be included in the form
>of so-called parameterization because it involves phenomena
>smaller in scale than the approximation grid used to describe
>the system.   Such models may be tweaked using observational
>data, but they are very far from being based on historical relations.
>Or at least this is what I understand.  But climate modelling is
>a sophisticated subject, constantly being improved, and I've
>probably oversimplified and ignored some important features.
 
         Yes, but I think when you hear La Nina means a wetter
than normal winter (or whatever) is likely in the US this is
just based on historical patterns.
 
>>          I also think it is possible to draw general conclusions
>> from the LTCM fiasco.  One is that it is dangerous to rely on
>> reputations.  The people involved in LTCM had glittering
>> reputations.  As a result their investors and creditors failed
>> to take reasonable precautions which could have averted much of
>> the trouble.
>
>Nonsense.  We rely on reputations all the time.  That is
>extrapolating from past experience, which usually is a good
>first guide.   But of course it is a mistake to rely solely
>on reputations.   We must examine what anyone says about a
>situation on its own merits.   We should also be careful not
>to assume that because someone is a proven expert in one area
>that what he or she says in a related area is necessarily
>correct.
 
         Ok, let me clarify to say it is dangerous to rely too
much on reputations.  You have (mostly properly in my opinion)
chastised posters to this group for ignoring expert opinion.
However it is also possible to give too much weight to expert
opinion, a danger you appear much less aware of.
 
>As best I can tell, LTCM strategy was based on sophisticated
>hedging schemes which supposedly avoided risk.   It also had
>to be done on a massive scale in order to succeed.  I think
>perhaps the only reasonable precaution their investors could
>have taken would have been not to invest.
 
         It had to use massive leverage to get impressive
returns.  Investors could have been asked more questions about
the trading strategy and not settled for answers like "If we
told you we would have to kill you" or "Only three people in
the world are capable of comprehending our strategy and they
all work for us".  I believe LTCM traded on its reputation to
avoid awkward questions.
 
>Financial schemes have a history of appearing to work in
>normal times and failing when things go awry, as they did
>in the Asian meltdown followed by the Russian failures.
>Perhaps LTCM had a more sophisticated scheme, so it may have
>worked better when it worked, but it is not surprising it
>eventually failed.   I attended a course on the Black Scholes
>model, and it was clear that it was based on several crucial
>assumptions which need not always apply.
 
         Lots of financial schemes are based on obtaining a
small gain most of the time at the risk of a small chance of
a huge loss.  They work fine until you roll the snake eyes.
LTCM had more to do with arrogance and greed than any failing
in Black Scholes.
 
>It is important however to distinguish between models in
>physical science and models in finance.   The former are based
>on physical laws which in their domain of relevance are
>hardly in doubt.  That doesn't mean that they can be used
>to be predict everything in all situation with certainty,
>but it does mean we should avoid false analogies with other
>kinds of models in other areas when deciding how accurate they
>may be.
 
         I don't agree.  Key parts of the climate models
are empirical (as you in fact discuss above).  There is no
essential difference between a climate model which is say 50%
fundamental laws and 50% empirical rules and an economic model
which is 100% empirical rules.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: LTCM, models and experts
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000213.113512.490@yktvmv.watson.ibm.com>
Date: Sun, 13 Feb 2000 16:35:12 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A1C751.1CC95808@math.nwu.edu>
   <jscanlon-65A2ED.18034209022000@news.linex.com> <38A30AA0.51210914@math.nwu.edu>
   <20000210.185321.351@yktvmv.watson.ibm.com> <38A42D1B.F00BCBCD@math.nwu.edu>
   <20000211.170840.688@yktvmv.watson.ibm.com> <38A58C0E.739C88B4@math.nwu.edu>
 
In article <38A58C0E.739C88B4@math.nwu.edu>,
 on Sat, 12 Feb 2000 10:36:30 -0600,
 Leonard Evens <len@math.nwu.edu> writes (in part):
>I think we have disagreed in the past about climate models
>and will continue to do so.   Since neither of us is a
>climatologist, I don't know what difference that makes to
>the science.   But I still think that any model has to be
>examined and criticized in its own right, not as part of
>a general criticism of models.   For climate models, for example,
>some conclusions may be more valid than others because they
>depend directly on physical principles.   In areas where
>empirical data may be used to tweak a model, one should
>have arguments about why such use may lead to inaccuracies
>or the opposite.   In other words, it is very important to
>look at details.
 
         I think this is where we disagree.  You are saying it is not
reasonable to generalize about models or in other words to construct
models of models (or modeling).  On the other hand I think it is useful
to see what can we say about models as a class before examining any
particular model.  For example models are all constructed by humans so
if humans are prone to certain types of errors then so will the models
they construct.  Also some models depend on complicated computer
calculations.  It is well established that large computer programs are
buggy (on the order of one bug per 100 lines of code is typical).  This
has to be allowed for in any estimate of model reliability.
         It is easy to say that every issue should be carefully
evaluated on its individual merits but no one has the time to do this.
So shortcuts must be found.  Relying on reputations is one such
shortcut and I agree it is sensible to do this (to some extent) even
though it is sometimes wrong.  I think there are other useful shortcuts
such as people are biased in favor of their interests or complicated
hard to verify models are suspect even though they may be wrong in
a particular case.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: LTCM, models and experts
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000214.151414.661@yktvmv.watson.ibm.com>
Date: Mon, 14 Feb 2000 20:14:14 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A1C751.1CC95808@math.nwu.edu>
   <jscanlon-65A2ED.18034209022000@news.linex.com> <38A30AA0.51210914@math.nwu.edu>
   <20000210.185321.351@yktvmv.watson.ibm.com> <38A42D1B.F00BCBCD@math.nwu.edu>
   <20000211.170840.688@yktvmv.watson.ibm.com> <38A58C0E.739C88B4@math.nwu.edu>
   <20000213.113512.490@yktvmv.watson.ibm.com> <38A70F63.6F011596@math.nwu.edu>
 
In article <38A70F63.6F011596@math.nwu.edu>,
 on Sun, 13 Feb 2000 14:09:07 -0600,
 Leonard Evens <len@math.nwu.edu> writes (in part):
>Let me comment on the issue of bugs in computer programs.
>I've written my share of programs and they certainly had
>bugs.  Some of these programs were designed to
>do calculations in an area of pure mathematics I work in.
>I've also constructed many arguments the old fashioned way.
>And my arguments are sometimes wrong.   At this point I'm
>not sure which is worse.   With a computer program, most
>bugs cause the program to fail or to give results which
>are obviusly wrong.  But on occasion, the program may appear
>to give correct results except in rare circumstances where
>the result may be plausible but is in fact wrong.   Conventional
>proofs on the other hand often hide misconceptions of
>the author.  A good rule of thumb is that if you are
>sufficiently clever to be able to convince yourself a
>false line of reasoning is correct, you can probably convince
>anyone else of it also.   ...
 
         I don't agree with this last line at all.  It is a
lot easier to put something over on yourself because you
want to believe it.
 
>                    ...   Errors in proofs constructed
>by professional mathematicians are not usually
>found by line by line examination of the argument but because
>they imply things which we know to be wrong.  ...
 
         To the extent that this is true I would say that it
largely reflects the fact that much of published mathematics
is not closely examined.  Published mathematics undoubtably
contains numerous errors which could be found by careful
examination but there is little incentive to do this.  When
there is incentive, such as for Andrew Wiles's original proof
of the Fermat conjecture, line by line examination revealed
a serious gap.
 
>                                         ...  Of course
>the same thing may be done in a computer program but it
>is harder since most programming does not involve assumptions
>about the subject matter of the program.   ...
 
         I don't understand what you are trying to say here.
Programming often involves assumptions such as "people's names
are not more than 30 characters long" or "people's names do
not contain characters like ! or $" about the subject matter.
 
>                                     ...   The only solution
>I can see to this dilemma is to come up with as many independent
>verifications of the result as one can.  In the case of a
>computer program, that might mean rewriting the program in
>another computer language on a different machine.  Or writing
>a program with internal logic completely unrelated to that
>of the original program.  In the case of a conventional
>proof, it means finding other proofs if possible.  In addition
>to all of this, if the results are important enough, others
>will try to reproduce them, and if they make errors, we
>can hope they will be different errors.
 
         I think errors can be found be examining proofs and
by reading code.
 
>I presume the situation is not that different in climate
>modelling.   And since it is such an important topic, I think
>we can presume that a lot of people will devote efforts both
>to constructing new models and also trying to determine how
>accurate they may be.
 
         It would help if the computer codes involved were freely
available.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Computers and SDI
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000214.154638.970@yktvmv.watson.ibm.com>
Date: Mon, 14 Feb 2000 20:46:38 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A58C0E.739C88B4@math.nwu.edu>
   <20000213.113512.490@yktvmv.watson.ibm.com> <38A70F63.6F011596@math.nwu.edu>
   <8890hj$9ge$1@saltmine.radix.net> <38A81F0A.589F1CB5@math.nwu.edu>
 
In article <38A81F0A.589F1CB5@math.nwu.edu>,
 on Mon, 14 Feb 2000 09:28:10 -0600,
 Leonard Evens <len@math.nwu.edu> writes:
>On an unrelated matter, I wonder about the state of computer programs
>to handle any of the latest proposed missile defense systems.
>When SDI was first proposed by Reagan, a leading expert on
>military computer systems argued that this was a one time use
>system which could never be tested in the circumstances in which
>it was to be used.  (I think his name is David Parnas---sp?)
>It would be interesting to know what the Pentagon has come up
>with for the latest systems.  Of course, these are designed
>supposedly only to shoot down a few missiles from a third
>rate poweer like North Korea, so they needn't be as complicated.
>Still many of their proponents have in mind an expansion to
>defend at least against a Chinese missile attack.   China if it finds
>it necessary can certainly opt for a large scale attack which
>would bring up the same issues.  Perhaps the idea would be to
>use three independent systems and believe two out of the three.
>But since they would necessarily have to share important
>common features, it is not clear how feasible this would be.
>
>There are of course vast differences between the use of
>complex computer systems for the military and the use of
>climate models to help make policy about fossil fuel use.
>But I suspect there are those who would support the use
>of computers in one of these contexts but not in the other.
>Perhaps it is a matter of whose computer is being in gored.
>(No puns intended!)
 
         One big difference is that nature cannot be bluffed but our
military opponents can be.  So it is not necessary for a military
system to actually work to be useful.  I think it is doubtful that an
SDI system would actually work very well if put to the test.  However I
do not think software is the main problem.
         As I recall Parnas' objections it seemed to me that he was
criticizing a strawman rather than a realistic proposal.  He was
considering a centralized system in which sensors would observe an
attack and send information back to some central command center which
would assign target lists and distribute them to antimissile satellites
which would then engage and destroy the enemy missiles.  I think this is
a poor design.  I think a more reasonable design would be distributed
with the antimissile satellites independently selecting and engaging
targets which would considerably simplify the software requirements
(not to mention the communication requirements).
         So in this context as well as others I favor keeping things
simple.  Particularly since I suspect software is not something the
military does well.
         Parnas also seemed to be trying to impose an unreasonable
performance requirement on the system namely that it would reliably
stop all missiles.  I think a good chance of stopping most of the
missiles is worthwhile (even ignoring the bluff aspect) especially in
the context of limited attacks.  Which is not to say that even this is
presently achievable or is likely to be in the near future.
         By the way I don't oppose the use of computers in climate
modeling or the use of climate models in evaluating policy options. I
do oppose relying on them unduly.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Computers and SDI
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000217.203804.026@yktvmv.watson.ibm.com>
Date: Fri, 18 Feb 2000 01:38:04 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A58C0E.739C88B4@math.nwu.edu>
   <88ctb8$11a$1@news.dgsys.com>
 
In article <88ctb8$11a$1@news.dgsys.com>,
 on 16 Feb 2000 01:08:56 GMT,
 jhalpern@ms1.dgsys.com (Joshua Halpern) writes:
>jbs@watson.ibm.com wrote:
>: In article <38A81F0A.589F1CB5@math.nwu.edu>,
>:  on Mon, 14 Feb 2000 09:28:10 -0600,
>:  Leonard Evens <len@math.nwu.edu> writes:
>: performance requirement on the system namely that it would reliably
>: stop all missiles.  I think a good chance of stopping most of the
>: missiles is worthwhile (even ignoring the bluff aspect) especially in
>: the context of limited attacks.  Which is not to say that even this is
>: presently achievable or is likely to be in the near future.
>
>I thought this was the goal of the original system, to stop
>decapitation first strikes by ensuring that an attacker could
>not count on wiping out all offensive missles (this of course,
>discounts the absurdities used in the political debate).
 
         Let's just say what the goals of the original system
should be was subject to debate.  Opponents liked to claim that
the goal should be perfect protection because that made it easier
to argue the system was impractical.  It seemed to me at the time
that Parnas was doing this (at least to some extent).  The whole
Parnas critique seemed a bit unreal to me.  It was as if somebody
had proposed a plane flying with antigravity motors and Parnas
had claimed, that's ridiculous you could never write the flight
control software.  Well maybe, but that's not the hard part.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Computers and SDI
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000218.215032.087@yktvmv.watson.ibm.com>
Date: Sat, 19 Feb 2000 02:50:32 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A58C0E.739C88B4@math.nwu.edu>
   <20000217.203804.026@yktvmv.watson.ibm.com> <88js4k$lnc$1@news3.infoave.net>
 
In article <88js4k$lnc$1@news3.infoave.net>,
 on 18 Feb 2000 16:31:16 GMT,
 swanson@nospam.com (Eric Swanson) writes:
>In article <20000217.203804.026@yktvmv.watson.ibm.com>, jbs@watson.ibm.com says...
 
         <snip>
 
>>         Let's just say what the goals of the original system
>>should be was subject to debate.  Opponents liked to claim that
>>the goal should be perfect protection because that made it easier
>>to argue the system was impractical.  It seemed to me at the time
>>that Parnas was doing this (at least to some extent).  The whole
>>Parnas critique seemed a bit unreal to me.  It was as if somebody
>>had proposed a plane flying with antigravity motors and Parnas
>>had claimed, that's ridiculous you could never write the flight
>>control software.  Well maybe, but that's not the hard part.
>
>Perhaps he was trying to point out that the launch software could
>never be tested until the plane were built and the first load of
>passengers, (270 million of us), were onboard and the plane was
>just reaching flight speed at the end of the runway......
>
>--
>Eric Swanson --- E-mail address: e_swanson@skybest.com   :-)
>--------------------------------------------------------------
 
         The Titanic lifeboat system was poorly designed, inadequately
tested and didn't work very well when needed.  It was still better
than nothing.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Computers and SDI
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000218.215823.568@yktvmv.watson.ibm.com>
Date: Sat, 19 Feb 2000 02:58:23 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A58C0E.739C88B4@math.nwu.edu>
   <88k786$d71$2@news.dgsys.com>
 
In article <88k786$d71$2@news.dgsys.com>,
 on 18 Feb 2000 19:40:54 GMT,
 jhalpern@ms1.dgsys.com (Joshua Halpern) writes:
>jbs@watson.ibm.com wrote:
 
         <snip>
 
>:          Let's just say what the goals of the original system
>: should be was subject to debate.  Opponents liked to claim that
>: the goal should be perfect protection because that made it easier
>: to argue the system was impractical.  It seemed to me at the time
>: that Parnas was doing this (at least to some extent).  The whole
>: Parnas critique seemed a bit unreal to me.  It was as if somebody
>: had proposed a plane flying with antigravity motors and Parnas
>: had claimed, that's ridiculous you could never write the flight
>: control software.  Well maybe, but that's not the hard part.
>
>Militarily it never made any sense except to protect against
>decapitation by a first strike attempt.  It is (was) obvious
>that the Soviet Union could have overwhelmed any city defense.
>Before you get too mad at Parnas, remember that the initial
>proposal was based on nuclear explosion driven X-Ray lasers
>which were postulated to work (by Teller when he sold the
>idea to Regan) using questionable results from an underground
>test.  When it became clear that it was BS, the program stepped
>through a rapidly changing array of kill weapon proposals that
>were shown one by one not to meet the mission requirements.
>In the latest iteration, the mission requirements have been
>changed.  I remain skeptical.
>
>josh halpern
 
         So the program failed for a bunch of technical and
political reasons which had nothing to do with the Parnas
critique which was just a distraction.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Computers and SDI
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000219.205919.262@yktvmv.watson.ibm.com>
Date: Sun, 20 Feb 2000 01:59:19 GMT
References: <87s5k6$j1d$1@nnrp1.deja.com> <38A58C0E.739C88B4@math.nwu.edu>
   <88k786$d71$2@news.dgsys.com> <20000218.215823.568@yktvmv.watson.ibm.com>
   <38AED5C4.4A7A77CD@math.nwu.edu>
 
In article <38AED5C4.4A7A77CD@math.nwu.edu>,
 on Sat, 19 Feb 2000 11:41:24 -0600,
 Leonard Evens <len@math.nwu.edu> writes:
>jbs@watson.ibm.com wrote:
 
         <snip>
 
>>          So the program failed for a bunch of technical and
>> political reasons which had nothing to do with the Parnas
>> critique which was just a distraction.
>>                         James B. Shearer
>
>But we spent a large amount of money on it first.   Parnas's
>argument was that even if the technical problems associated
>with the proposed exotic weapons systems could be solved, there
>was still a remaining problem which could not be solved.
 
         What does "could not be solved" mean here?  It doesn't
mean known to be impossible like trisecting an angle (with ruler
and compass used in certain ways).  It doesn't even mean believed
to be impossible according to our current understanding of nature
like faster than light travel.  So it can just mean beyond the
current state of the art.  Even if this were true (which I
doubt given reasonable requirements on the software) it certainly
wasn't anywhere near as far beyond the current state of the art
as atomic bomb pumped X-ray lasers for example.  So I continue
to think Parnas wasn't contributing anything useful to the
debate.
 
>Also to respond to a previous assertion, Parnas did not say
>that the system had to be 100 percent effective to be effective.
>But how much less than 100 percent would have been worth it.
>There is no question that Reagan had proposed a system to
>protect American population centers.  I don't think it would
>have received too much support from the general population
>had it been advertised as 50 or 75 percent or even 90 percent
>effective, since that could have resulted in massive destruction
>of all our important urban centers.  I think Parnas's
>objection spoke directly to the system that was proposed to
>the public.
 
         You are trying to impose unreasonable requirements.
The government requires seat belts and air bags which are no
where near 100% effective.  Cops wear bullet proof vests
which aren't 100% effective.
         Btw I think what Reagan actually proposed was that the
US attempt to develop a system to protect population centers.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Faster Rate of Global Warming
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000226.173923.485@yktvmv.watson.ibm.com>
Date: Sat, 26 Feb 2000 22:39:23 GMT
References: <jscanlon-C2665B.17211722022000@news.linex.com>
   <_VRs4.1260$Xk2.9212@tor-nn1.netcom.ca> <38b42303$0$88068@news.execpc.com>
   <6l0t4.926$%P5.26489@typhoon.we.rr.com> <38b57c38$0$1402@news.execpc.com>
   <oEht4.1491$%P5.35651@typhoon.we.rr.com> <38b5f109$0$88068@news.execpc.com>
   <kfDt4.1658$%P5.43591@typhoon.we.rr.com>
 
In article <kfDt4.1658$%P5.43591@typhoon.we.rr.com>,
 on Fri, 25 Feb 2000 22:21:04 GMT,
 "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
 
         <snip>
 
>Now let's talk about political reality.  You know as well as I do that there
>is no chance of a worldwide energy or fuel tax.  What we really have are
>governmental command and control decisions, like them or not.  Those
>decisions tend to be correlated because some governments fund research that
>is then used worldwide, because of worldwide opinion, and because of
>treaties.  What I see in your post is basically special pleading for a
>particular industry.  Well, we'll have it out in the court of public
>opinion, and you will lose, because your economic fundamentals are just not
>there.
 
         I don't see your point here.  There may be little chance of
a uniform global carbon tax but there is equally little chance of
uniform government command and control decisions.  Individual
government tax decisions will tend to be correlated for the same
reasons as command and control decisions.  So why the preference
for command and control decisions?  Is it just the environmentalist
taste for ordering people around?
         As for favoring particular industries you are of course
free to argue that nuclear waste is as big a problem as CO2 emissions
in which case favoring nuclear over fossil would not be sensible.
Is that in fact what you believe?
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: "Global Warming" Article ?
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000301.192520.997@yktvmv.watson.ibm.com>
Date: Thu, 2 Mar 2000 00:25:20 GMT
References: <891gk3$o68$1@news3.infoave.net>
   <8tvkbsglm7n5anqktb3kd415amm9nhklaj@4ax.com> <89ebdr$fu1$1@news3.infoave.net>
   <x4hln45j8ix.fsf@Steam.Stanford.EDU> <38BB0B49.969C6D8E@math.nwu.edu>
   <x4hd7pgkev3.fsf@Steam.Stanford.EDU> <qTHu4.59$ql2.2832@typhoon.we.rr.com>
   <x4hzoskeg2r.fsf@Steam.Stanford.EDU> <v92v4.2156$ql2.16084@typhoon.we.rr.com>
   <x4hbt4zaysh.fsf@Steam.Stanford.EDU> <eYdv4.2908$ql2.22513@typhoon.we.rr.com>
   <x4hvh36z9uz.fsf@Steam.Stanford.EDU> <Ymhv4.3259$ql2.23786@typhoon.we.rr.com>
 
In article <Ymhv4.3259$ql2.23786@typhoon.we.rr.com>,
 on Wed, 01 Mar 2000 23:05:28 GMT,
 "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
>"John McCarthy" <jmc@Steam.Stanford.EDU> wrote:
 
         <snip>
 
>> 2. Let me remind you that the thread started with whether and how
>> Western Europe might survive a cessation of the gulf stream.  As I
>> wrote, I examine how problems might be solved and Puchalsky
>> concentrates on assigning blame.
>>
>
>The solution to the problem is obvious, at least on a large scale.  It is to
>gradually ramp down CO2 emissions through efficiency and conservation
>measures, plus an increasing investment in renewable energy sources.  You
>don't like that solution, though; you'd rather recommend that Western Europe
>greenhouse (literally) most of its agricultural land.  Assigning blame has
>nothing to do with it; I'm simply pointing out that you're rejecting a real
>solution because of your ideology, while suggesting an unworkable one.
 
         This is not a solution to a cessation of the gulf stream.  It
might make cessation less likely.  It does not specify what to do if
cessation occurs nevertheless.  So it should not be directly compared
McCarthy's proposal.
         As for ideology you appear at least as influenced by ideology
as McCarthy.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: "Global Warming" Article ?
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000302.195827.713@yktvmv.watson.ibm.com>
Date: Fri, 3 Mar 2000 00:58:27 GMT
References: <89ebdr$fu1$1@news3.infoave.net>
   <x4hln45j8ix.fsf@Steam.Stanford.EDU> <38BB0B49.969C6D8E@math.nwu.edu>
   <x4hd7pgkev3.fsf@Steam.Stanford.EDU> <qTHu4.59$ql2.2832@typhoon.we.rr.com>
   <x4hzoskeg2r.fsf@Steam.Stanford.EDU> <v92v4.2156$ql2.16084@typhoon.we.rr.com>
   <x4hbt4zaysh.fsf@Steam.Stanford.EDU> <eYdv4.2908$ql2.22513@typhoon.we.rr.com>
   <x4hvh36z9uz.fsf@Steam.Stanford.EDU> <Ymhv4.3259$ql2.23786@typhoon.we.rr.com>
   <20000301.192520.997@yktvmv.watson.ibm.com> <LTmv4.3806$ql2.28668@typhoon.we.rr.com>
 
In article <LTmv4.3806$ql2.28668@typhoon.we.rr.com>,
 on Thu, 02 Mar 2000 05:21:47 GMT,
 "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
><jbs@watson.ibm.com> wrote:
>>  "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
>> >The solution to the problem is obvious, at least on a large scale.  It is
>to
>> >gradually ramp down CO2 emissions through efficiency and conservation
>> >measures, plus an increasing investment in renewable energy sources.  You
>> >don't like that solution, though; you'd rather recommend that Western
>Europe
>> >greenhouse (literally) most of its agricultural land.  Assigning blame
>has
>> >nothing to do with it; I'm simply pointing out that you're rejecting a
>real
>> >solution because of your ideology, while suggesting an unworkable one.
>>
>>          This is not a solution to a cessation of the gulf stream.  It
>> might make cessation less likely.  It does not specify what to do if
>> cessation occurs nevertheless.
>
>My proposed solution can be done now.  McCarthy's has to wait until after
>catastrophe.  I think it's better to try to prevent catastrophe.
>
>And McCarthy's "solution" is not so much of a solution as an ideological
>claim that anything can be fixed, especially if you ignore economics.  As
>such it functions as an argument against implementing any real solution.
>Why try prevention if you can fix anything that happens?
 
         McCarthy's solution is more of a claim that nothing has an
infinite cost which is entirely correct.
         When considering whether to take preventive measures against
some possible event it is useful to consider the cost of the event
and the probability that it will occur if nothing is done and compare
this with the cost of the preventive measures.
         It may suffice to crudely bound the cost of the event.  This
is what McCarthy was doing.  He suggested himself that it would
probably be cheaper to import the food.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Patrick Michaels slams Thomas Karl and NCDC
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,sci.geo.meteorology
Message-ID: <20000304.200026.212@yktvmv.watson.ibm.com>
Date: Sun, 5 Mar 2000 01:00:26 GMT
References: <89nftg$ml2$1@brokaw.wa.com> <952105153snz@deltrak.demon.co.uk>
   <yvZv4.5477$ql2.50527@typhoon.we.rr.com>
 
In article <yvZv4.5477$ql2.50527@typhoon.we.rr.com>,
 on Sat, 04 Mar 2000 01:18:22 GMT,
 "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
>"Andrew Stephenson" <ames@deltrak.demon.co.uk> wrote:
>> In article <89nftg$ml2$1@brokaw.wa.com> blackbox@bbox.com "Jim
>> Galasyn" writes:
>>
>> > Patrick Michaels criticizes the recent NCDC report �...�
>>
>> And what, pray, is a Patrick Michaels when it's at home?  Is its
>> opinion worth losing sleep over?
>
>Patrick Michaels is a well-known "Tobacco Institue" type scientist who
>flacks for the coal industry.
 
         Bit of a cheap shot.
         Michaels is actually a professor at the University of
Virginia who (according to him) receives 20% of his funding from the
fossil fuel industry.
         For an interesting account of his ethics complaint against
a newspaper for deriding his scientific credibility see
 
<a href="http://www.mtn.org/~newscncl/determinations/det_118.html>
 
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: sci.env: some threads never change
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000304.210314.465@yktvmv.watson.ibm.com>
Date: Sun, 5 Mar 2000 02:03:14 GMT
References: <x4hd7pgkev3.fsf@Steam.Stanford.EDU>
   <qTHu4.59$ql2.2832@typhoon.we.rr.com> <x4hzoskeg2r.fsf@Steam.Stanford.EDU>
   <v92v4.2156$ql2.16084@typhoon.we.rr.com> <x4hbt4zaysh.fsf@Steam.Stanford.EDU>
   <eYdv4.2908$ql2.22513@typhoon.we.rr.com> <x4hvh36z9uz.fsf@Steam.Stanford.EDU>
   <Ymhv4.3259$ql2.23786@typhoon.we.rr.com> <20000301.192520.997@yktvmv.watson.ibm.com>
   <LTmv4.3806$ql2.28668@typhoon.we.rr.com> <20000302.195827.713@yktvmv.watson.ibm.com>
   <_YZv4.5489$ql2.50851@typhoon.we.rr.com>
 
In article <_YZv4.5489$ql2.50851@typhoon.we.rr.com>,
 on Sat, 04 Mar 2000 01:49:46 GMT,
 "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
>�Subject header changed from "'Global Warming' article?"�
>
><jbs@watson.ibm.com> wrote:
>>  "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
>> >And McCarthy's "solution" is not so much of a solution as an ideological
>> >claim that anything can be fixed, especially if you ignore economics.  As
>> >such it functions as an argument against implementing any real solution.
>> >Why try prevention if you can fix anything that happens?
>>
>>          McCarthy's solution is more of a claim that nothing has an
>> infinite cost which is entirely correct.
>
>Nonsense.   You can define the words "infinite cost" so that the phrase
>"nothing has an infinite cost" is tautologically correct.  But there are all
>sorts of things that no amount of money or other resources can repair.  No
>amount of money will bring your deceased family members back to life.
>McCarthy's science fiction notwithstanding, no amount of money will bring an
>extinct species back to life.   No jerry-rigged technocratic solution can
>really undo all the damage of turning Western Europe into Scandinavia.
 
         How would you define cost so that some (but not all) things
do have an infinite cost?
         By the way my claim about infinite cost is empirical not
tautological.  In my framework people could put an infinite value on
living forever (for example) but in practice they don't.
 
>Your next step will be to argue that society effectively puts a price on
>saving the lives of people's family members, on saving endangered species,
>and on turning Western Europe into Scandinavia.  Perhaps *your* imagined
>society makes decisions based strictly on cost-benefit comparisons.  I'm
>glad that I don't actually live in such a barbarous society.  But given most
>anti-environmentalists' demonstrated incompetence at any kind of economic
>analysis, I'd say that you really fail even at your own standard of
>decision-making.   There is no way that McCarthy "puts crude bounds on"
>costs; he simply assumes that they don't exist.
 
         My imagined society would make decisions based on rational
analysis rather than emotional appeals.  Perhaps you feel this would
be to your disadvantage.
         As for incompetence at economic analysis strangely enough
professional economists seem to believe this is characteristic of
environmentalists as opposed to their opponents.
         As for McCarthy I doubt he claims his proposals are cost
free.  He specifically said his greenhouses would be "expensive".
 
>I remember Alan McGowen writing about McCarthy here once.  He said that even
>politicians had a better understanding of these issues, because if you
>showed them plans to build hundreds of trillions of dollars of nuclear power
>plants, desalination units, endangered species cloning labs, greenhoused
>agricultural areas, topsoil movers, and all of the other trash that McCarthy
>refers to as "solutions", they'd ask why we couldn't just get along with the
>free services that the environment provides now.  All we have to do is
>accomplish the much easier technological task of refraining from destroying
>them.  That pretty much sums it up.
 
         Politicians judge arguments by how they would play in a thirty
second TV ad.  I agree with them that McCarthy's ideas would not go
over well in such a format (much easier and safer to just deny global
warming is worth worrying about).  This does not mean they are
worthless.  This after all is supposed to be a sci group.
         Refraining from altering the environment is not so easy if
you also wish to provide a growing standard of living for the world's
billions.  Ceasing to use fossil fuels would be easy enough
technologically but appears impossible politically.
         As I have said before I expect fossil fuels to be used until
they are physically exhausted.  I see little reason to believe marginal
changes in time scale to make any real difference in the climate
effects.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: sci.env: some threads never change
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000306.181923.117@yktvmv.watson.ibm.com>
Date: Mon, 6 Mar 2000 23:19:23 GMT
References: <x4hzoskeg2r.fsf@Steam.Stanford.EDU>
   <v92v4.2156$ql2.16084@typhoon.we.rr.com> <x4hbt4zaysh.fsf@Steam.Stanford.EDU>
   <eYdv4.2908$ql2.22513@typhoon.we.rr.com> <x4hvh36z9uz.fsf@Steam.Stanford.EDU>
   <Ymhv4.3259$ql2.23786@typhoon.we.rr.com> <20000301.192520.997@yktvmv.watson.ibm.com>
   <LTmv4.3806$ql2.28668@typhoon.we.rr.com> <20000302.195827.713@yktvmv.watson.ibm.com>
   <_YZv4.5489$ql2.50851@typhoon.we.rr.com> <20000304.210314.465@yktvmv.watson.ibm.com>
   <SAxw4.6954$ql2.76691@typhoon.we.rr.com>
 
In article <SAxw4.6954$ql2.76691@typhoon.we.rr.com>,
 on Sun, 05 Mar 2000 18:21:38 GMT,
 "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
><jbs@watson.ibm.com> wrote
>>          How would you define cost so that some (but not all) things
>> do have an infinite cost?
>
>I'll remind you that you are the one who introduced the phrase "infinite
>cost".  What I said was that McCarthy was arguing that anything could be
>fixed.  If you define cost as the amount of money (representing resources)
>that must be spent to do something, you could spend all the money in the
>world and not accomplish certain tasks.  Mathematical quibbles aside, for
>all practical purposes that is infinite cost.
 
         Actually I think you have a point about my introduction of
"infinite cost" since on further reflection I don't think that is
what McCarthy is arguing.  Nor do I think he is arguing anything
can be fixed in the sense of restored to its original condition
(since as you point out this is often impossible).  Instead I think
he is arguing many problems can be ameliorated by technology and
that this should be taken into account when deciding how much effort
we should devote to avoiding such problems.
         Also I should have said infinite value not infinite cost
since as you point out some tasks can require arbitrarily large
amounts of resources to accomplish.
 
>>          By the way my claim about infinite cost is empirical not
>> tautological.  In my framework people could put an infinite value on
>> living forever (for example) but in practice they don't.
>
>That's because they can't.  It's silly to spend all of your effort on living
>forever when you know that you're going to fail anyway.
 
         Well of course that is a thought experiment.
         People (or society) behave as if nothing has infinite value
to them but this is not logically required by the utility framework.
People could value the second million as much as the first million
but they don't.
 
>>          My imagined society would make decisions based on rational
>> analysis rather than emotional appeals.  Perhaps you feel this would
>> be to your disadvantage.
>
>As I said, your society would be a barbarous one in which money was the only
>standard of value.  You would define any reference to anything except money
>as an "emotional appeal".
 
         My society would be different and you are of course free to
believe any society different from yours is barbarous.
 
>>          As for McCarthy I doubt he claims his proposals are cost
>> free.  He specifically said his greenhouses would be "expensive".
>
>Oh, that really works at bounding the cost of those things.  I read a recent
>article on a desalination plant built in southern California.  They claim
>somewhere around $1,600 per acre-foot as their cost of water.  They have
>never run the plant.  Someone pointed out that as long as farmers are
>trading water in the central Valley at $100 to $200 per acre-foot, that
>desalinization plant would never run.
 
         Well that depends.  One might think that if farmland is
selling for $1000 an acre, land for subdivisions shouldn't cost much
more than that.  But because some people have the notion that
farmland shouldn't be freely convertible to suburbs there are often
legal impediments to selling farmland for subdivisions.  As a result
the market price for subdivision land can greatly exceed the market
price for farmland.
         Similarly there are often impediments to shifting water from
farm use to urban use.  In many cases the farmers don't actually own
the water, they just are accustomed to buying it from some government
agency at some ridiculously low price.  Naturally they don't want
competition from people willing to pay more.  Rational analysis
might show some water should be diverted from farm use to urban use
but emotional appeals from farmers might prevent this.  In which case
the desalinization plant might get run.  Incidentally, why was it
built?
 
>>          Refraining from altering the environment is not so easy if
>> you also wish to provide a growing standard of living for the world's
>> billions.
>
>Nonsense.  The world's billions do not get a growing standard of living by
>adopting economic policies that destroy their local environments.
 
         They might in the short run even if you are correct in the
long run.  Anyway to state my point in another way, the reason we
can't rely solely on the earth's natural environmental services is
that these services have a certain capacity and unfortunately the
world population is well over that capacity.
 
>>          As I have said before I expect fossil fuels to be used until
>> they are physically exhausted.  I see little reason to believe marginal
>> changes in time scale to make any real difference in the climate
>> effects.
>
>It's very easy to argue that nothing should be done if you start with the
>assumption that nothing will be done.  As far as I can tell, you have no
>scientific evidence to suggest that marginal changes in time scale would
>make no difference.
 
         Well of course you can never be sure a small change won't make a
big difference.
         However my understanding of the science is that the amount of
climate change will be primarily determined by the total amount of CO2
emitted and is not particularly sensitive to the exact emission
schedule.  Anyone care to comment on this?
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: sci.env: some threads never change
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000307.205811.192@yktvmv.watson.ibm.com>
Date: Wed, 8 Mar 2000 01:58:11 GMT
References: <x4hbt4zaysh.fsf@Steam.Stanford.EDU>
   <eYdv4.2908$ql2.22513@typhoon.we.rr.com> <x4hvh36z9uz.fsf@Steam.Stanford.EDU>
   <Ymhv4.3259$ql2.23786@typhoon.we.rr.com> <20000301.192520.997@yktvmv.watson.ibm.com>
   <LTmv4.3806$ql2.28668@typhoon.we.rr.com> <20000302.195827.713@yktvmv.watson.ibm.com>
   <_YZv4.5489$ql2.50851@typhoon.we.rr.com> <20000304.210314.465@yktvmv.watson.ibm.com>
   <SAxw4.6954$ql2.76691@typhoon.we.rr.com> <20000306.181923.117@yktvmv.watson.ibm.com>
   <3J_w4.9849$ql2.105960@typhoon.we.rr.com>
 
In article <3J_w4.9849$ql2.105960@typhoon.we.rr.com>,
 on Tue, 07 Mar 2000 03:30:07 GMT,
 "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
><jbs@watson.ibm.com> wrote:
 
         <snip>
 
>>          My society would be different and you are of course free to
>> believe any society different from yours is barbarous.
>
>You are advocating a society in which the only basis for decision-making is
>economic.  That is simply a varient of might makes right, except that money
>is substituted for physical power.  I can't think of any better word for
>that than "barbarous".
 
         First I am not advocating a society in which the only basis
for decision making is economic.  Society has to make many decisions
which are not primarily economic.  For example what the age of consent
should be.
         Second all governments ultimately rely on physical power to
enforce their rules.  Do you think the current US society is
barbarous?  How about the US in 1950, 1900, 1850 or 1800?
 
         <snip>
 
>>          Well of course you can never be sure a small change won't make a
>> big difference.
>>          However my understanding of the science is that the amount of
>> climate change will be primarily determined by the total amount of CO2
>> emitted and is not particularly sensitive to the exact emission
>> schedule.  Anyone care to comment on this?
>
>The marginal changes could make a difference in the total amount emitted.
>Assume that at some year, 20xx, another technology is developed that
>generates very cheap non-fossil power.  Even nuclear if you like; the exact
>form isn't important.  Assuming a speedy conversion due to economic reasons,
>CO2 emissions will tail off drastically after 20xx.  Marginal changes in the
>emission rate prior to 20xx can then make large differences in the total
>emissions.  And the earlier the marginal change, the greater the total
>effect.
 
         In another post you asserted your belief that renewal energy
would become cheaper than fossil fuels.  I see no reason at all to
expect this.  What renewal energy sources do you expect to displace
natural gas for home heating, oil for transportation and coal for
electric power generation in the US?
         Sure it is possible some very cheap energy source will
quickly displace fossil fuels at some point.  I don't think it is
very likely however.  There aren't any plausible candidates.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: sci.env: some threads never change
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000308.220234.617@yktvmv.watson.ibm.com>
Date: Thu, 9 Mar 2000 03:02:34 GMT
References: <Ymhv4.3259$ql2.23786@typhoon.we.rr.com>
   <20000301.192520.997@yktvmv.watson.ibm.com> <LTmv4.3806$ql2.28668@typhoon.we.rr.com>
   <20000302.195827.713@yktvmv.watson.ibm.com> <_YZv4.5489$ql2.50851@typhoon.we.rr.com>
   <20000304.210314.465@yktvmv.watson.ibm.com> <SAxw4.6954$ql2.76691@typhoon.we.rr.com>
   <20000306.181923.117@yktvmv.watson.ibm.com> <3J_w4.9849$ql2.105960@typhoon.we.rr.com>
   <20000307.205811.192@yktvmv.watson.ibm.com> <yCwx4.3627$HN.235845@bgtnsc06-news.ops.worldnet.att.net>
 
In article <yCwx4.3627$HN.235845@bgtnsc06-news.ops.worldnet.att.net>,
 on Wed, 08 Mar 2000 18:04:14 GMT,
 "Richard Puchalsky" <rpuchalsky@att.net> writes:
><jbs@watson.ibm.com> wrote:
>>  "Richard Puchalsky" <rpuchalsky@mediaone.net> writes:
>> >You are advocating a society in which the only basis for decision-making
>is
>> >economic.  That is simply a varient of might makes right, except that
>money
>> >is substituted for physical power.  I can't think of any better word for
>> >that than "barbarous".
>>
>>          First I am not advocating a society in which the only basis
>> for decision making is economic.  Society has to make many decisions
>> which are not primarily economic.  For example what the age of consent
>> should be.
>
>If deciding about what to do about endangered species or about changing the
>climate of Europe is primarily economic, then surely the age of consent is
>too.  I'm sure that you could get sellers of contraceptives, psychologists,
>and various other experts and affected parties together to decide what age
>of consent would maximize economic growth, given the need to balance sales
>against psychological damage that could harm sales later.  Anything else
>would be an "emotional appeal" in your termanology.
 
         Deciding what to do about endangered species is an economic
question because there is general agreement that it is undesirable
for species to go extinct.  Similarly there is general agreement
that pollution or the glaciation of Europe is undesirable.  Society
has many desires but finite resources.  Deciding how to allocate
scarce resources is an economic (and political also of course)
question.  Note as society becomes richer we may expect it to
allocate more resources to reducing pollution, preserving endangered
species etc.  On the other hand deciding an age of consent is not
about allocating scarce resources so is not an economic question
(although it may have some minor economic effects).  There is no
reason to expect the age of consent to change in any particular way
as society becomes richer.
         Of course some environmental issues are not economic.  For
example environmentalists may desire an environment as close to
"natural" as possible while people like McCarthy may desire an
environment heavily modified so as to be as pleasing to humans as
possible.  Such conflicting goals are a political issue not an
economic issue.
         You also seem to be suggesting that I believe anything
other than economic analysis is an emotional appeal.  This is not
not the case.
 
>>          Second all governments ultimately rely on physical power to
>> enforce their rules.  Do you think the current US society is
>> barbarous?  How about the US in 1950, 1900, 1850 or 1800?
>
>That is a complete non sequiter.  All governments rely, if necessary, on
>physical power to enforce rules.  All governments do *not* declare that
>physical power is the only basis for *creating* rules.
 
         Well, I said rules should be created based on rational
arguments rather than emotional appeals and you declared this was a
variant of might makes right.  I fail to see this.
 
>>          In another post you asserted your belief that renewal energy
>> would become cheaper than fossil fuels.  I see no reason at all to
>> expect this.  What renewal energy sources do you expect to displace
>> natural gas for home heating, oil for transportation and coal for
>> electric power generation in the US?
>
>First of all, not every use has to be displaced.  The critical one is
>electricity generation; oil for transportation could be replaced by
>electricity, hydrogen, or biomass-derived alcohol in any case.  Home heating
>could be done by electricity or natural gas could be left as a relic use; by
>itself it's not big enough use to keep the CO2 level from starting to drop.
 
         For electricity to displace oil for transportation or natural
gas for heating it would have to become substantially cheaper than it
is now since it is currently far from competitive.  In fact I believe
currently electricity would be uncompetitive with gasoline for cars
even if it were free.  So you are asking renewables not just to beat
coal for electricity but to beat it substantially which is even
harder.
 
>The economic advantage of many renewable energy sources is that, once the
>physical plant is built, no fuel needs to be provided and no waste needs to
>be carried away (until the physical plant is itself recycled).  Solar, wind,
>hydropower, and geothermal all have this advantage.  I find it difficult to
>believe that, given another couple of decades of efficiency improvements and
>power storage improvements, that won't make these forms of power undisputed
>winners.
 
         Hydropower and geothermal have limited capacity and cannot
displace coal.  Wind and solar have the major problem that they do
not produce power on demand.  This means they cannot displace coal
without a major improvement in power storage.  Furthermore the best
wind sites have limited capacity and solar is currently nowhere near
being competitive in price.
         As for technology improvements, people have been looking
for better ways to store power for a hundred years, I see no reason
to expect a breakthrough in the next twenty.  I don't see any reason
to expect big improvements in wind either, windmills have been around
for a long time.  Solar has somewhat better prospects for major
improvements but it also has a lot further to go.  I don't see it
becoming competitive.
         Remember also fossil fuels are not standing still.
Generators are becoming more efficient and mining technology is also
improving.  Also note if fossil fuels start to be displaced this
will depress their price slowing further shifts.
         I think the chance fossil fuels will become undisputed
losers in the next twenty years is essentially zero, less than 1%.
Actually if you really believe they will be displaced starting in
20 years then there is little to worry about.
 
>Biomass and waste burning don't have these advantages, which is why I expect
>them to be relegated to niche markets.
 
         There is some prospect for breakthroughs in the biomass area
because genetic engineering is a new technology which may allow major
improvements.  Of course this is a bit ironic considering the
environmentalist opinion of this technology.
 
>I remember that I didn't specify renewables in the last post -- I just said
>non-fossil.  And if McCarthy can play science fiction, so can I.  I see no
>reason to imagine that there will be some eternal technical barrier
>preventing us from building fusion power plants.  I expect that variations
>in the Earth's magnetic field, causing loss of the magnetic bottle, could be
>compensated for by throwing large enough quantities of real-time computing
>power at the problem.  Fusion plants at least create minor amounts of
>radioactive waste, and it's difficult to see how they could "melt down" in a
>Chernobyl fashion.
 
         Your first reply to McCarthy said renewable saying in part:
 
>I'd guess very high, say 90 percent.  As technological progress goes on, it
>will become unequivocally cheaper to build renewable sources of energy, even
>without global climate change concerns.  At that point places like China
>will convert for economic reasons.
 
         As for fusion, the barrier is economic not technical.  Fusion
is much harder than fission hence can be expected to be much more
expensive.  Also as far I know loss of the magnetic bottle has nothing
whatever to do with variations in the earth's magnetic field.  If the
plasma is unstable any small fluctuation will run away.
         Fusion power has a whole host of technical, political and
economic problems and seems likely to remain science fiction for
the foreseeable future.
                      James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: sci.env: some threads never change
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000311.190832.321@yktvmv.watson.ibm.com>
Date: Sun, 12 Mar 2000 00:08:32 GMT
References: <LTmv4.3806$ql2.28668@typhoon.we.rr.com>
   <20000302.195827.713@yktvmv.watson.ibm.com> <_YZv4.5489$ql2.50851@typhoon.we.rr.com>
   <20000304.210314.465@yktvmv.watson.ibm.com> <SAxw4.6954$ql2.76691@typhoon.we.rr.com>
   <20000306.181923.117@yktvmv.watson.ibm.com> <3J_w4.9849$ql2.105960@typhoon.we.rr.com>
   <20000307.205811.192@yktvmv.watson.ibm.com> <yCwx4.3627$HN.235845@bgtnsc06-news.ops.worldnet.att.net>
   <20000308.220234.617@yktvmv.watson.ibm.com> <Jgvy4.4965$Q76.347101@bgtnsc06-news.ops.worldnet.att.net>
 
In article <Jgvy4.4965$Q76.347101@bgtnsc06-news.ops.worldnet.att.net>,
 on Sat, 11 Mar 2000 17:21:45 GMT,
 "Richard Puchalsky" <rpuchalsky@att.net> writes:
><jbs@watson.ibm.com> wrote:
>>  "Richard Puchalsky" <rpuchalsky@att.net> writes:
>> >If deciding about what to do about endangered species or about changing
>the
>> >climate of Europe is primarily economic, then surely the age of consent
>is
>> >too.  I'm sure that you could get sellers of contraceptives,
>psychologists,
>> >and various other experts and affected parties together to decide what
>age
>> >of consent would maximize economic growth, given the need to balance
>sales
>> >against psychological damage that could harm sales later.  Anything else
>> >would be an "emotional appeal" in your termanology.
>>
>>          Deciding what to do about endangered species is an economic
>> question because there is general agreement that it is undesirable
>> for species to go extinct.
>
>I have to say that that is a nonsensical description of what makes a
>question economic.  Take almost any political problem now current in the
>U.S. -- social security, medicare, national defense, etc. -- and you will
>find general agreement that it is undesirable for people to go poor, to go
>without medical care, or for the country to be poorly defended.  General
>agreement that some things are undesirable is not a criterion for making
>issues apolitical.
 
         Generally economic questions are also political.  Economics
is about allocating resources.  People have different views on what
society should do with its resources.  Deciding between competing
views is a political problem.
         Many political questions are economic, how to divide up the
pie.  Many others are not.  For example in the US, should abortion
be legal, should marriage be between one man and one woman only,
should English be the official language, what powers the police
should have etc.
 
>> >That is a complete non sequiter.  All governments rely, if necessary, on
>> >physical power to enforce rules.  All governments do *not* declare that
>> >physical power is the only basis for *creating* rules.
>>
>>          Well, I said rules should be created based on rational
>> arguments rather than emotional appeals and you declared this was a
>> variant of might makes right.  I fail to see this.
>
>Who gets to decide what a "rational argument" is?  One James B. Shearer?  I
>thought so.
 
         While I would like to see society respond more to rational
arguments than emotional appeals I don't have any magic bullet for
how to achieve this.  Emotional appeals are prevalent because they
work.  So I suppose I would prefer a society in which more people
think like I do in which case emotional appeals would be less
successful.
 
>Imagine that you are a legislator in western Europe.  The legislature is
>debating global climate change policy.  No one really knows the possible
>costs involved, just as in reality.  You get up and say "I value the
>continued existence of our land as is has been for generations much more
>highly than the amount of money we'd lose!  How can those who love our land
>agree with drastically changing it?"
>
>Now is that a rational argument or not, oh great judge?  If so, please tell
>us exactly how it is distinguished from an "emotional appeal".
 
         Most political advocacy is a mixture of rational arguments
and emotional appeals (with some slanting of the facts thrown in).
Certainly there are rational arguments for concern about CO2
emissions.  Appeals to tradition however are often suspect.
Consider, "I value the continued existence of our culture and values
as they have been for generations.  How can those who love our nation
agree to allow an influx of aliens with different values who will
radically alter our culture?"  Does Puchalsky consider this
argument equally legitimate?
 
>>          For electricity to displace oil for transportation or natural
>> gas for heating it would have to become substantially cheaper than it
>> is now since it is currently far from competitive.  In fact I believe
>> currently electricity would be uncompetitive with gasoline for cars
>> even if it were free.
>�...�
>>          Hydropower and geothermal have limited capacity and cannot
>> displace coal.  Wind and solar have the major problem that they do
>> not produce power on demand.  This means they cannot displace coal
>> without a major improvement in power storage.
>�...�
>>          As for technology improvements, people have been looking
>> for better ways to store power for a hundred years, I see no reason
>> to expect a breakthrough in the next twenty.
>
>So your answer is technological pessimism.  I should ask that noted
>technological optimist John McCarthy to argue with you -- no, strangely
>enough, in another post he's also saying things about how  people have been
>thinking about wind power for thirty years and therefore the technology is
>as developed as it's ever going to get.  Why the sudden pessimism from such
>noted believers?
>
>Could it be -- (gasp) -- that they themselves are much like the person
>resisting change in my example above?  Except that they are less honest,
>because they don't admit that that is what they are doing.
 
         Fossil fuels are technology also.  McCarthy has argued and
I agree that there are alternatives which would allow us to sustain
a technological civilization.  This does not mean they are likely
to be cheaper than fossil fuels.
         I have no particular emotional commitment to fossil fuels,
if an alternative wins out in the market (like compact discs beat
records) so be it.  I don't think it's likely however.
 
>>          I think the chance fossil fuels will become undisputed
>> losers in the next twenty years is essentially zero, less than 1%.
>> Actually if you really believe they will be displaced starting in
>> 20 years then there is little to worry about.
>
>I said the year 20xx in my example.  And of course you have no scientific
>evidence to show that changing emission levels in the next 20 years would
>not make a critical difference even if emissions dropped thereafter.
 
         I have no proof of course that a slight reduction over the
next twenty years won't avert some disaster.  Similarly you have no
proof that business as usual is bound to cause a disaster.
         However I expect if fossil fuels were going to start running
out in 20 years there would be considerably less concern about CO2
emissions.
 
>I cut the last bit where you say that fusion power won't work.  What a
>surprise.  I myself would be much more surprised if fusion somehow could not
>be made to work within the next century.
 
         I said won't work economically an important qualification.
You can believe what you want, however people have been working on
fusion power for about 50 years with basically no progress whatever.
Solar power is more plausible than fusion.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: calling all sci.env regulars -- power calculation
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000315.234529.396@yktvmv.watson.ibm.com>
Date: Thu, 16 Mar 2000 04:45:29 GMT
References: <rx7zos3kfew.fsf@muon.astro.psu.edu>
   <fVXy4.6656$7L.439406@bgtnsc04-news.ops.worldnet.att.net> <rx7ya7mkcf1.fsf@muon.astro.psu.edu>
   <t0bz4.9893$Q76.632934@bgtnsc06-news.ops.worldnet.att.net> <38CDA207.7BBA49C8@home.com>
   <cLhz4.784$mf.47495@bgtnsc05-news.ops.worldnet.att.net> <38CDBE00.7CCD1747@home.com>
   <SJkz4.754$qN1.61692@bgtnsc04-news.ops.worldnet.att.net> <38CE0201.8A20CC4F@home.com>
   <5Dtz4.1757$mf.117180@bgtnsc05-news.ops.worldnet.att.net> <38D05155.F9EF8323@home.com>
 
In article <38D05155.F9EF8323@home.com>,
 on Thu, 16 Mar 2000 03:13:29 GMT,
 Gregory Greenman <morbius@home.com> writes:
 
         <snip>
 
>You keep saying that my derivation is "trash".  Well for the umpteenth
>time - here it is - POINT OUT WHAT'S WRONG!!!
 
         A jet engine works by throwing stuff out the back.  So the
engine is applying a force not just to the plane but to the exhaust. I
believe this has to be taken into account in figuring the work the
engine is doing.  You are not doing this, hence it appears to me that
your derivation is incorrect.
         Consider the following simple example.  Suppose you push on a
wall.  The wall does not move so you are doing no work.  Now push on
the the front wall of a moving train.  It may appear you are now doing
work.  But in reality you are not.  Why?  Because in order to push on
the front wall of the train you must be applying an equal and opposite
force to the floor of the train.  The floor of the train moves the same
distance as the front wall so in computing the work you are doing you
get two terms that exactly cancel (since the force terms are equal in
magnitude and opposite in sign).
         You must compute things in this way for the work to be
independent of the inertial frame of reference as it should be.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: calling all sci.env regulars -- power calculation
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000316.144921.262@yktvmv.watson.ibm.com>
Date: Thu, 16 Mar 2000 19:49:21 GMT
References: <rx7ya7mkcf1.fsf@muon.astro.psu.edu>
   <t0bz4.9893$Q76.632934@bgtnsc06-news.ops.worldnet.att.net> <38CDA207.7BBA49C8@home.com>
   <cLhz4.784$mf.47495@bgtnsc05-news.ops.worldnet.att.net> <38CDBE00.7CCD1747@home.com>
   <SJkz4.754$qN1.61692@bgtnsc04-news.ops.worldnet.att.net> <38CE0201.8A20CC4F@home.com>
   <5Dtz4.1757$mf.117180@bgtnsc05-news.ops.worldnet.att.net> <38D05155.F9EF8323@home.com>
   <20000315.234529.396@yktvmv.watson.ibm.com> <38D08F2F.A1AB7F19@home.com>
 
In article <38D08F2F.A1AB7F19@home.com>,
 on Thu, 16 Mar 2000 07:37:22 GMT,
 Gregory Greenman <morbius@home.com> writes:
>jbs@watson.ibm.com wrote:
>
>> In article <38D05155.F9EF8323@home.com>,
>>  on Thu, 16 Mar 2000 03:13:29 GMT,
>>  Gregory Greenman <morbius@home.com> writes:
>>
>>          <snip>
>>
>> >You keep saying that my derivation is "trash".  Well for the umpteenth
>> >time - here it is - POINT OUT WHAT'S WRONG!!!
>>
>>          A jet engine works by throwing stuff out the back.  So the
>> engine is applying a force not just to the plane but to the exhaust. I
>> believe this has to be taken into account in figuring the work the
>> engine is doing.  You are not doing this, hence it appears to me that
>> your derivation is incorrect.
>
>NO - I defined the work that I was talking about as the useful work
>that the engine was doing on the plane.  The work that the engine
>is doing on the plane is dependent on the force it exerts on the plane.
>
>Yes - there is energy going into the exhaust.  In addition to the
>forces involved - there is heat energy in the exhaust.  However, as
>I have repeatedly said to Richard - the work that I am talking about
>is the work the engine does on the plane.  The rate at which the
>engine does work on the plane is the product of the force and the
>velocity.
 
         Ok, let me rephrase my objection in your terminology.  Some of
the thrust of the engine is expended overcoming the drag on the engine.
This drag is unavoidable because the engine is air breathing.  So the
force doing useful work on the plane will be less than the rated
thrust of the engine.
         This assumes the rated thrust of a jet engine is determined
by measurement on a stationary test stand not by measurement while
hanging off the wing of a 747 in cruise flight.  Anyone know the
exact procedure for determining the rated thrust?
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: calling all sci.env regulars -- power calculation
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000317.184926.567@yktvmv.watson.ibm.com>
Date: Fri, 17 Mar 2000 23:49:26 GMT
References: <cLhz4.784$mf.47495@bgtnsc05-news.ops.worldnet.att.net>
   <38CDBE00.7CCD1747@home.com> <SJkz4.754$qN1.61692@bgtnsc04-news.ops.worldnet.att.net>
   <38CE0201.8A20CC4F@home.com> <5Dtz4.1757$mf.117180@bgtnsc05-news.ops.worldnet.att.net>
   <38D05155.F9EF8323@home.com> <SD0A4.47$hE5.778@news.get2net.dk>
   <GZ0A4.2904$iP.208948@bgtnsc04-news.ops.worldnet.att.net> <rx7wvn2ixrv.fsf@muon.astro.psu.edu>
   <hhbA4.3943$iP.262712@bgtnsc04-news.ops.worldnet.att.net> <rx7n1nxipr9.fsf@muon.astro.psu.edu>
 
In article <rx7n1nxipr9.fsf@muon.astro.psu.edu>,
 on 17 Mar 2000 10:24:10 -0500,
 Steinn Sigurdsson <steinn@muon.astro.psu.edu> writes:
 
         <snip>
 
>Ok.
>Consider a 747 cruising in level flight.
>The engines are running at less than full throttle, their
>power output is less than the power rating of the engine
>(a 747 can fly with 1 engine and cruise with 2 engines,
>it normally has 4 engines)
>The rate of work done on the airplane is the drag force
>times the airspeed, and all the power necessary to maintain
>this comes from the engines.
>
>Now: the pilot moves the engines to full throttle,
>while maintaining constant altitude.
>
>The engines are now instantaneously going at full thrust,
>and the power output per engine is the airspeed - the cruise velocity,
>times the rated thrust of the engine.
>
>This is Greenman's calculation. It is correct.
>The only implicit assumption is that the engine can
>actually operate at maximum thrust at the cruise velocity.
 
         This calculation may be approximately correct in this case.
It is not exactly correct because it is ignoring the work the engine
is doing on the exhaust.  The power output of the engine depends on
all of the work it is doing.  You can not just take part.  Suppose you
are riding in an airplane and push on the seat in front of you.  It is
invalid to invoke P = F * v and say you are producing a lot of power.
You must also include the work you are doing on your seat which in
this case exactly cancels so your power output is zero.  If your
seat moves back as you push on the seat in front then the work done
will not exactly cancel but both terms must be included to calculate
your power output.  Similarly for the jet engine you must include the
work the engine does on the exhaust.  It may be for cruise flight
(in the frame of reference of the surrounding air) that the work
the engine does on the exhaust is small compared to the work the
engine does on the plane and can be neglected, however there is
certainly no reason for it to be exactly zero.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: calling all sci.env regulars -- power calculation
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000317.201329.738@yktvmv.watson.ibm.com>
Date: Sat, 18 Mar 2000 01:13:29 GMT
References: <t0bz4.9893$Q76.632934@bgtnsc06-news.ops.worldnet.att.net>
   <38CDA207.7BBA49C8@home.com> <cLhz4.784$mf.47495@bgtnsc05-news.ops.worldnet.att.net>
   <38CDBE00.7CCD1747@home.com> <SJkz4.754$qN1.61692@bgtnsc04-news.ops.worldnet.att.net>
   <38CE0201.8A20CC4F@home.com> <5Dtz4.1757$mf.117180@bgtnsc05-news.ops.worldnet.att.net>
   <38D05155.F9EF8323@home.com> <20000315.234529.396@yktvmv.watson.ibm.com>
   <38D08F2F.A1AB7F19@home.com> <20000316.144921.262@yktvmv.watson.ibm.com>
   <38D23344.E0FDCBC0@home.com>
 
In article <38D23344.E0FDCBC0@home.com>,
 on Fri, 17 Mar 2000 13:29:41 GMT,
 Gregory Greenman <morbius@home.com> writes:
>jbs@watson.ibm.com wrote:
>
>> In article <38D08F2F.A1AB7F19@home.com>,
>>  on Thu, 16 Mar 2000 07:37:22 GMT,
>>  Gregory Greenman <morbius@home.com> writes:
>> >jbs@watson.ibm.com wrote:
>> >
>> >> In article <38D05155.F9EF8323@home.com>,
>> >>  on Thu, 16 Mar 2000 03:13:29 GMT,
>> >>  Gregory Greenman <morbius@home.com> writes:
>> >>
>> >>          <snip>
>> >>
>> >> >You keep saying that my derivation is "trash".  Well for the umpteenth
>> >> >time - here it is - POINT OUT WHAT'S WRONG!!!
>> >>
>> >>          A jet engine works by throwing stuff out the back.  So the
>> >> engine is applying a force not just to the plane but to the exhaust. I
>> >> believe this has to be taken into account in figuring the work the
>> >> engine is doing.  You are not doing this, hence it appears to me that
>> >> your derivation is incorrect.
>> >
>> >NO - I defined the work that I was talking about as the useful work
>> >that the engine was doing on the plane.  The work that the engine
>> >is doing on the plane is dependent on the force it exerts on the plane.
>> >
>> >Yes - there is energy going into the exhaust.  In addition to the
>> >forces involved - there is heat energy in the exhaust.  However, as
>> >I have repeatedly said to Richard - the work that I am talking about
>> >is the work the engine does on the plane.  The rate at which the
>> >engine does work on the plane is the product of the force and the
>> >velocity.
>>
>>          Ok, let me rephrase my objection in your terminology.  Some of
>> the thrust of the engine is expended overcoming the drag on the engine.
>> This drag is unavoidable because the engine is air breathing.  So the
>> force doing useful work on the plane will be less than the rated
>> thrust of the engine.
>>          This assumes the rated thrust of a jet engine is determined
>> by measurement on a stationary test stand not by measurement while
>> hanging off the wing of a 747 in cruise flight.  Anyone know the
>> exact procedure for determining the rated thrust?
>>                         James B. Shearer
>
>James,
>
>    I think our only disagreement is one of semantics.  Basically,
>what do you do about the drag the engine adds to the plane.
 
         No, I have another objection (which is different so I
should not have said I was rephrasing my objection).  The power
output of the engine depends on all the work it is performing,
on the exhaust and on the plane.  It is not valid to take part
of this work, label it useful and ignore the rest (which may be
negative reducing the total power output).
         Consider the case of a rocket engine.  A rocket (in a
vacuum) will have a constant thrust independent of its speed.
This does not mean it will produce arbitrarily large amounts
of power when attached to objects going arbitrarily fast.  The
rocket is also doing work on its exhaust.  If the object to
which it is attached is moving more than half the speed of the
exhaust (where the speed of the exhaust is measured relative to
the rocket) then this work will be negative (since the kinetic
energy of the exhaust will be less after being shot out of the
rocket than it was before).  In fact figured properly the power
output of the rocket will be constant no matter how fast it is
going.  This also means the power output is independent of the
inertial frame of reference as it should be.
         Now it may be for the case of a jet engine in cruise
flight (in the reference frame of the surrounding air) that the
work done on the exhaust is small (relative to the work done on
the plane) and can be neglected.  However it is not obvious that
this is so, so there is no reason to insult people who do not
immediately see that this is the case.  Nor does it help to
claim that an approximate calculation is actually exact.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: calling all sci.env regulars -- power calculation
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000318.215150.417@yktvmv.watson.ibm.com>
Date: Sun, 19 Mar 2000 02:51:50 GMT
References: <38CDBE00.7CCD1747@home.com>
   <SJkz4.754$qN1.61692@bgtnsc04-news.ops.worldnet.att.net> <38CE0201.8A20CC4F@home.com>
   <5Dtz4.1757$mf.117180@bgtnsc05-news.ops.worldnet.att.net> <38D05155.F9EF8323@home.com>
   <SD0A4.47$hE5.778@news.get2net.dk> <GZ0A4.2904$iP.208948@bgtnsc04-news.ops.worldnet.att.net>
   <rx7wvn2ixrv.fsf@muon.astro.psu.edu> <hhbA4.3943$iP.262712@bgtnsc04-news.ops.worldnet.att.net>
   <rx7n1nxipr9.fsf@muon.astro.psu.edu> <20000317.184926.567@yktvmv.watson.ibm.com>
   <rx74sa4i3ym.fsf@muon.astro.psu.edu>
 
In article <rx74sa4i3ym.fsf@muon.astro.psu.edu>,
 on 18 Mar 2000 12:27:13 -0500,
 Steinn Sigurdsson <steinn@muon.astro.psu.edu> writes:
 
         <snip>
 
>BTW do I recall that you really suggested that work
>done should be invariant between different inertial
>reference frames? That is trivially not the case.
 
         Yes, that was me.
         It seems to me that if the engine is not accelerating
itself the forces it is exerting must sum to 0.  This means
adding some v to all the velocities (to change frames) will make
no difference in the total work (although of course it will
change the components).  What trivial error am I making?
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: calling all sci.env regulars -- power calculation
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000321.010246.046@yktvmv.watson.ibm.com>
Date: Tue, 21 Mar 2000 06:02:46 GMT
References: <38CE0201.8A20CC4F@home.com>
   <5Dtz4.1757$mf.117180@bgtnsc05-news.ops.worldnet.att.net> <38D05155.F9EF8323@home.com>
   <SD0A4.47$hE5.778@news.get2net.dk> <GZ0A4.2904$iP.208948@bgtnsc04-news.ops.worldnet.att.net>
   <rx7wvn2ixrv.fsf@muon.astro.psu.edu> <hhbA4.3943$iP.262712@bgtnsc04-news.ops.worldnet.att.net>
   <rx7n1nxipr9.fsf@muon.astro.psu.edu> <20000317.184926.567@yktvmv.watson.ibm.com>
   <rx74sa4i3ym.fsf@muon.astro.psu.edu> <20000318.215150.417@yktvmv.watson.ibm.com>
   <rx7ya7dh6de.fsf@muon.astro.psu.edu>
 
In article <rx7ya7dh6de.fsf@muon.astro.psu.edu>,
 on 20 Mar 2000 12:57:17 -0500,
 Steinn Sigurdsson <steinn@muon.astro.psu.edu> writes:
>jbs@watson.ibm.com writes:
>
>> In article <rx74sa4i3ym.fsf@muon.astro.psu.edu>,
>>  on 18 Mar 2000 12:27:13 -0500,
>>  Steinn Sigurdsson <steinn@muon.astro.psu.edu> writes:
>
>>          <snip>
>
>> >BTW do I recall that you really suggested that work
>> >done should be invariant between different inertial
>> >reference frames? That is trivially not the case.
>
>>          Yes, that was me.
>>          It seems to me that if the engine is not accelerating
>> itself the forces it is exerting must sum to 0.  This means
>> adding some v to all the velocities (to change frames) will make
>> no difference in the total work (although of course it will
>> change the components).  What trivial error am I making?
>
>Anyway, consider the following system:
>
>you watch a long train run by, going at constant speed
>in a straight line.
>On the aisle of the train, there is a toy block, connected
>to a winch at the back of the train (the train is long
>and much more massive than the train).
>The winch is pulling the block backwards through the
>train at the same linear speed as the train is moving
>forward across the ground.
>The carpet on the aisle is rough.
>
>Now is there any work being done on the block from
>your point of view?
>Is there work being done from the point of view of a
>person sitting on a seat in the train?
 
         Let v be the speed of the train.  Let F be the frictional
force the carpet is exerting on the block.  Then -F will be the
force the winch is exerting on the block.  Also the winch will be
be exerting a force of F on the back of the train.
         Now from the point of view of an observor beside the track
the train is moving at speed v and the block is stationary.  So the
winch is doing 0 work on the block and work at rate Fv on the train.
So the power output of the winch is Fv.
         On the other hand from the point of view of an observor on
the train the train is stationary and the block is moving with speed
-v.  So the winch is doing 0 work on the train and work at rate Fv
(Fv=(-F)(-v)) on the block.  So the power output of the winch is
Fv again.
         So the total work does not change as we change frames, just
the way in which is divided up between work on the block and work
on the train.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: calling all sci.env regulars -- power calculation
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000321.194749.857@yktvmv.watson.ibm.com>
Date: Wed, 22 Mar 2000 00:47:49 GMT
References: <38D05155.F9EF8323@home.com> <SD0A4.47$hE5.778@news.get2net.dk>
   <GZ0A4.2904$iP.208948@bgtnsc04-news.ops.worldnet.att.net> <rx7wvn2ixrv.fsf@muon.astro.psu.edu>
   <hhbA4.3943$iP.262712@bgtnsc04-news.ops.worldnet.att.net> <rx7n1nxipr9.fsf@muon.astro.psu.edu>
   <20000317.184926.567@yktvmv.watson.ibm.com> <rx74sa4i3ym.fsf@muon.astro.psu.edu>
   <20000318.215150.417@yktvmv.watson.ibm.com> <rx7ya7dh6de.fsf@muon.astro.psu.edu>
   <20000321.010246.046@yktvmv.watson.ibm.com> <rx7pusogwg6.fsf@muon.astro.psu.edu>
 
In article <rx7pusogwg6.fsf@muon.astro.psu.edu>,
 on 21 Mar 2000 10:43:53 -0500,
 Steinn Sigurdsson <steinn@muon.astro.psu.edu> writes:
>jbs@watson.ibm.com writes:
>
>> In article <rx7ya7dh6de.fsf@muon.astro.psu.edu>,
>>  on 20 Mar 2000 12:57:17 -0500,
>>  Steinn Sigurdsson <steinn@muon.astro.psu.edu> writes:
>> >jbs@watson.ibm.com writes:
>
>> >> In article <rx74sa4i3ym.fsf@muon.astro.psu.edu>,
>> >>  on 18 Mar 2000 12:27:13 -0500,
>> >>          <snip>
>
>
>> >>          It seems to me that if the engine is not accelerating
>> >> itself the forces it is exerting must sum to 0.  This means
>> >> adding some v to all the velocities (to change frames) will make
>> >> no difference in the total work (although of course it will
>> >> change the components).  What trivial error am I making?
> ...
>> >you watch a long train run by, going at constant speed
>> >in a straight line.
>> >On the aisle of the train, there is a toy block, connected
>> >to a winch at the back of the train (the train is long
>> >and much more massive than the train).
>> >The winch is pulling the block backwards through the
>> >train at the same linear speed as the train is moving
>> >forward across the ground.
>> >The carpet on the aisle is rough.
>
>> >Now is there any work being done on the block from
>> >your point of view?
>> >Is there work being done from the point of view of a
>> >person sitting on a seat in the train?
>
> >          Let v be the speed of the train.  Let F be the frictional
> > force the carpet is exerting on the block.  Then -F will be the
> > force the winch is exerting on the block.  Also the winch will be
> > be exerting a force of F on the back of the train.
> >          Now from the point of view of an observor beside the track
> > the train is moving at speed v and the block is stationary.  So the
> > winch is doing 0 work on the block and work at rate Fv on the train.
> > So the power output of the winch is Fv.
> >          On the other hand from the point of view of an observor on
> > the train the train is stationary and the block is moving with speed
> > -v.  So the winch is doing 0 work on the train and work at rate Fv
> > (Fv=(-F)(-v)) on the block.  So the power output of the winch is
> > Fv again.
> >          So the total work does not change as we change frames, just
> > the way in which is divided up between work on the block and work
> > on the train.
>
>Interesting way of looking at it.
>Now throw out the winch, and run the rope out the
>back of the train and tie it to a mountain...
 
         Now the block is a source of drag on the train.  It is
dissipating energy as heat at rate Fv.  So the train's engine
will have to increase its power output by Fv to maintain a
constant velocity.
 
>Also consider the following - according to the
>track side observer, the winch is doing no work on
>the block - yet the underside of the block is getting warm.
 
         The heat is produced by friction.  Here the power to
overcome the friction is produced by the winch rather than by
the train.
         Friction is caused by the difference in velocities.
It does not matter if we see the winch as dragging the block
past the train or dragging the train past the block the heat
produced will be the same.
                   James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Tooth Fairy - "I want to believe" (was Re: $ WINDPOWER vs NUKES$)
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,talk.environment,alt.save.the.earth
Message-ID: <20000324.161424.871@yktvmv.watson.ibm.com>
Date: Fri, 24 Mar 2000 21:14:24 GMT
References: <38D4504F.B9585A38@home.com> <38D4A8A4.C9701AFA@home.com>
   <38D77259.7422390F@home.com> <38D77F10.EA202BC8@home.com>
   <yZLB4.14869$Xk2.62449@tor-nn1.netcom.ca> <38D7AD3E.DB8CE3C2@tds.net>
   <5XRB4.15131$Xk2.62632@tor-nn1.netcom.ca> <38D8285
   <o1ZB4.14777$iP.1014089@bgtnsc04-news.ops.worldnet.att.net> <8b9vg6$bd4$1@mulga.cs.mu.OZ.AU>
   <38D886FA.96CEB73C@tds.net> <KO6C4.15163$iP.1059615@bgtnsc04-news.ops.worldnet.att.net>
   <38DB1122.AE62E23E@home.com> <RRNC4.15835$9M1.1036693@bgtnsc06-news.ops.worldnet.att.net>
 
In article <RRNC4.15835$9M1.1036693@bgtnsc06-news.ops.worldnet.att.net>,
 on Fri, 24 Mar 2000 17:46:25 GMT,
 "Richard Puchalsky" <rpuchalsky@att.net> writes:
>"Gregory Greenman" <morbius@home.com> wrote:
>>
>> P = F * V  that is Power = Force * Velocity.
>>
>
>As per usual,  Greenman fails to provide any justification for why the
>equation that he uses above, using the maximum force of the engine and the
>cruising velocity of a plane that the engine happens to be mounted on,
>should produce a number equal to the rated power of the engine.
>
>Nor has he explained the deriviation of a 0.62 conversion factor from
>maximum thrust to horsepower that he said should be easy to explain.  Of
>course he didn't know what he was talking about in that instance.
>
>Nor has he explained why his power of 71 MW for the jet engine is correct,
>when two justified methods of calculating the power of the same engine give
>a number from 15-30 MW.
>
>Greenman is a walking, posting disadvertisement for M.I.T.  Anyone else
>would know how ludicrous it is to keep posting the derivation for P= F * v,
>when the power produced by that equation is not the power that is relevant
>for the comparison needed in the problem at hand.  Greenman is the worst
>physicist that I've ever encountered.
 
         For what it's worth this is my view of the problem.
         First let us consider a rocket because it is simpler.
 
Assume the rocket engine is mounted on a fixed test stand.
 
         Let m be the fuel flow rate (mass/time).
         Let -s be the exhaust velocity (distance/time).
         Let P be the power output of the engine.
         Let F be the force or thrust of the engine.
 
Then we have
 
         (1)  P = .5 * m * s * s
         (2)  F = m * s
 
         (1) follows because this is the rate at which the engine
is changing the kinetic energy of the exhaust (there is a pressure
term too which I am ignoring).  Since the engine is not moving the
force it is exerting is doing no work.
         (2) follows because this is the (negative of the) rate
at which the engine is changing the momentum of the exhaust.
 
Now suppose we mount the rocket engine on a rocket.
 
         Let v be the velocity of the rocket.
         So the velocity of the exhaust is now (v-s).
 
Now we have
 
         (3) P = F * v + .5 * m * (v-s) ** 2 - .5 * m * v ** 2
         (4) F = m * (v - (v-s))
 
          In (3) F * v is the work per unit time (or power) that
the rocket engine is doing on the rocket and the remaining terms
are the work (per unit time) the engine is doing on the exhaust.
Note when v > s/2 the work done on the exhaust is negative (since
the kinetic energy of the exhaust is less than the kinetic energy
of the fuel in this case).
 
Now let us simplify (4) and substitute in (3) to obtain
 
         (5) P = .5 * m * s ** 2
         (6) F = m * s
 
         (5) and (6) are independent of v, hence the same as (1) and
(2) which assumed v = 0.  So although the F * v work the engine is
doing on the rocket can become arbitrarily large this does not mean the
rocket engine is arbitrarily powerful.  As v increases the work done
on the exhaust becomes negative to maintain constant total power.  In
effect some of the kinetic energy of the fuel is transferred to the
rocket.
         So Puchalsky's objection to Greenman's calculation is valid
in theory, for large v just including the F * v term will give a
nonsensical answer.  However note the kinetic energy of a subsonic
plane's fuel is much less than the chemical energy so Greenman's
calculation might survive in an approximate sense.  Let us see.
 
Consider a jet engine on a plane.
 
         Let m be the fuel flow rate (mass/time).
         Let r be the mass ratio exhaust/fuel.
         Let s be the exhaust velocity (distance/time).
         Let v be the plane velocity.
         Let P be the power output of the engine.
         Let F be the force or thrust of the engine.
 
Note s is now the absolute (not relative) exhaust velocity.  Also we
assume the incoming air has velocity 0.  The power and thrust are:
 
         (7) P = F * v -.5 * m * v ** 2 + .5 * m * r * s ** 2
         (8) F = m * v - m * r * s
 
Solving (8) for r * s and substituting in (7) gives
 
         (9) P = F * (v - s/2) - .5 * m * v ** 2 + .5 * m * v * s
 
Solving (8) for s and substituting in the last term of (9) gives
 
         (10) P = F*(v-v/(2*r)-s/2) - .5*m*v**2 + .5*m*v**2/r
 
Now in a jet engine r >> 1 (since O is most of the mass of H2O or
CO2 and air is only .2 O and some of the air is bypassed)
So we may drop the 1/r terms leaving
 
         (11) P == F * (v - s/2) - .5 * m * v ** 2
 
Now .5 * m * v ** 2 is just the kinetic energy of the fuel.  As
noted above this will be much less than the chemical energy of
the fuel for a subsonic plane so this term can go leaving
 
         (12) P == F * (v - s/2)
 
Now consider a plane at cruise velocity.  Then s << v so
 
         (12) P == F * v
 
which is Greenman's formula.  There is one remaining problem,
as Sigurdsson has noted, can a jet engine produce maximum
thrust at cruising speed.  I suspect not, since a jet needs
maximum thrust while taking off (low speed and dense air) not
while cruising (high speed and thin air).  In fact, don't jets
sometimes have trouble taking off from high altitude fields in
hot weather because the thinner air limits their thrust?
 
Alternatively consider a stationary jet preparing to release
its brakes and take off.  Here v will be 0 so (12) becomes
 
         (13) P == -.5 * F * s
 
So if we make some SWAGS that the jet can develop its maximum
thrust in this situation and that s, the exhaust velocity (of a
stationary jet engine), can be approximated by -v we obtain the
alternate approximation
 
          (14) P == .5 * F * v
 
which I suspect might be a bit better.
         So, although Puchalsky is correct that Greenman's derivation
is not exactly correct, it should not give a wildly wrong answer in
this situation.  Also this whole argument is a bit of a distraction.
You can look up the power output of commercial gas turbines.  This
will show the power output of a large wind farm or nuclear power plant
can be obtained with a small number of gas turbines.  This is bad news
for both wind and nuclear if gas is the competition.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Tooth Fairy - "I want to believe" (was Re: $ WINDPOWER vs NUKES$)
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,talk.environment,alt.save.the.earth
Message-ID: <20000325.122450.873@yktvmv.watson.ibm.com>
Date: Sat, 25 Mar 2000 17:24:50 GMT
References: <yZLB4.14869$Xk2.62449@tor-nn1.netcom.ca>
   <38D7AD3E.DB8CE3C2@tds.net> <5XRB4.15131$Xk2.62632@tor-nn1.netcom.ca>
   <38D8285 <o1ZB4.14777$iP.1014089@bgtnsc04-news.ops.worldnet.att.net>
   <8b9vg6$bd4$1@mulga.cs.mu.OZ.AU> <38D886FA.96CEB73C@tds.net>
   <KO6C4.15163$iP.1059615@bgtnsc04-news.ops.worldnet.att.net> <38DB1122.AE62E23E@home.com>
   <RRNC4.15835$9M1.1036693@bgtnsc06-news.ops.worldnet.att.net> <20000324.161424.871@yktvmv.watson.ibm.com>
   <0_WC4.19001$mf.1473668@bgtnsc05-news.ops.worldnet.att.net>
 
In article <0_WC4.19001$mf.1473668@bgtnsc05-news.ops.worldnet.att.net>,
 on Sat, 25 Mar 2000 04:09:32 GMT,
 "Richard Puchalsky" <rpuchalsky@att.net> writes:
><jbs@watson.ibm.com> wrote:
>>          For what it's worth this is my view of the problem.
>>          First let us consider a rocket because it is simpler.
>
>Cool, an actual derivation!
>
>>
>> Assume the rocket engine is mounted on a fixed test stand.
>>
>>          Let m be the fuel flow rate (mass/time).
>
>You are using this in a kinetic energy calculation; why then is it the fuel
>rate?  Most of the exhaust is air, not fuel.
 
         A rocket (at least the rocket I am considering here) does not
burn air, it carries all of its fuel (say liquid O2 and liquid H2 for
example) and all of its exhaust is former fuel.  This is why it will
work in a vacuum.  It also makes the calculations simpler as I said.
         As for the comment (by Sigurdsson) that the problem with
high altitude takeoffs is lack of lift rather than lack of thrust,
this sounds plausible.  Oh well.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Record year for nuclear power
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,talk.environment,alt.save.the.earth
Message-ID: <20000414.141822.917@yktvmv.watson.ibm.com>
Date: Fri, 14 Apr 2000 18:18:22 GMT
References: <x4hd7nt5por.fsf@Steam.Stanford.EDU>
 
In article <x4hd7nt5por.fsf@Steam.Stanford.EDU>,
 on 13 Apr 2000 20:25:40 -0700,
 John McCarthy <jmc@Steam.Stanford.EDU> writes:
 
        <snip>
        [regarding nuclear construction costs]
 
>The worst cost a lot more than planned; the best came in under
>budget.  Assuming people learn from experience, best previous results
>is a better predictor of the future than the worst.
 
         You have made this argument before and it is not accurate.
The groups trying to drive up costs learn from experience also.
 
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: Wages and Guest Worker Visas
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,sci.econ,alt.politics.economics,sci.research.careers
Message-ID: <20000416.173848.736@yktvmv.watson.ibm.com>
Date: Sun, 16 Apr 2000 21:38:48 GMT
References: <8crsr6$rir$3@mohawk.hwcn.org> <38F21763.9EE@facstaff.wisc.edu>
   <8ct8f9$khl$1@onsager.bd.psu.edu> <38F28DA6.AD1C888D@facstaff.wisc.edu>
   <8cubbr$n3n$1@onsager.bd.psu.edu> <38F3DB35.CC658486@dgs.dgsys.com>
   <38F47BC0.725A@facstaff.wisc.edu> <38F522CE.6A660FEA@dgs.dgsys.com>
   <8d350c$7uj$0@216.155.0.50> <38F79685.70BD@facstaff.wisc.edu>
   <38F7D4A1.54BFFB06@dgs.dgsys.com> <38F8CAB5.10CEEC5@facstaff.wisc.edu>
   <38F93E35.ABC7E2D8@dgs.dgsys.com>
 
In article <38F93E35.ABC7E2D8@dgs.dgsys.com>,
 on Sun, 16 Apr 2000 00:14:46 -0400,
 Halpern <jbh@dgs.dgsys.com> writes:
>Jim Blair:
>> > I think it clear that marriage benefits society, and I see no problem in
>> > the tax code encouraging it.  It is single women trying to raise kids
>> > that 'cost' society.  By increased poverty and crime.
>Halpern wrote:
>
>> > Yes, let's eliminate the possibility of divorce..
>> It does not follow that just because marriage is a benefit to society, that
>> divorce should be impossible.  I'll let you figure out why. And most single women
>> raising children are not divorced.  And the divorced ones have the help of child
>> support payments.
>
>Many single women raising children ARE divorced.  In 1995 for example, of the
>approximately 70  million children in the US, 69% lived with both parents, of the
>remaining 23 % lived with their mother, 4% with the father, and 4% with neither.
>Of the 23% 9% were in divorced families, 6% were married, but the spouse was
>absent 8% never married, and 1% were widowed.  So the majority of women
>raising children alone ARE either divorced or living without their spouse (that
>covers a lot of sins like separated, deserted, etc.). You might also consult with
>various advocacy groups as to how often child support payments are made,
>what the amounts are, etc..
 
         Which category includes children living with their mother and
step father?
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: PBS, Nova, Frontline Special on Climate
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,sci.geo.meterorology,sci.environment
Message-ID: <20000421.120837.928@yktvmv.watson.ibm.com>
Date: Fri, 21 Apr 2000 16:08:37 GMT
References: <jscanlon-CEC070.20423219042000@news.linex.com>
   <8doq9c$1kk$1@quark.scn.rain.com> <390049A6.165C4F11@math.nwu.edu>
 
In article <390049A6.165C4F11@math.nwu.edu>,
 on Fri, 21 Apr 2000 07:29:26 -0500,
 Leonard Evens <len@math.nwu.edu> writes:
>"Peter S.F. Wilson" wrote:
>>
>> I agree the special was well done. I was shocked they allowed an industry
>> spokesman on the show. I have one question though. There was a lot of talk
>> about the H2O gas positive feedback. As the climate heats up more water is
>> vaporized leading to more warming as H2O is the most important greenhouse
>> gas. The climate has warmed in the past. So why didn't that feedback take
>> over and lead to catastrophic warming. I saw that the warming was less in
>> the past but that shouldn't affect the feedback. I thought the program
>> skewed toward the believers and Al Gore is a moron. Somebody should grill
>> him on the science of global warming.
>> PSFW
>
>Many positive feedback processes exhibit such an effect.
>For small changes the feedback is strongly positive, but
>then other factors may intervene which limit the growth of the
>response.  And it may not be easy to describe what happens in
>words without analyzing a mathematical model.
>With a simple linear model, what you describe would
>happen, but the actual processes are complex and non-linear.
>One must try to avoid being misled by oversimplified explanations.
 
>Clearly there have got to be upper limits to such effects, since
>nothing ever grows to infinity in a finite time.  For example,
>Venus, which could be described as a case of a runaway greenhouse
>effect, does have a stable average temperature under current
>conditions.  Similarly, one could call the present situation
>on Earth a "runaway greenhouse effect" since the average temperature
>is some 60 deg C warmer than would be the case were there no
>CO_2 or other greenhouse gases (except water vapor) in the
>atmosphere.  Some paleoclimatologists conjecture that at
>various times in the past, the oceans were frozen and life
>just barely survived while CO_2 levels slowly rose and
>eventually the Earth warmed again.   So, if that happened,
>clearly something must have damped the feedback effect.
>Just how such damping effects would work is a function
>of the details of the processes and may not be simply explainable
>in words.   That is what mathematics and modelling is for.
 
         This is mostly wrong.  Small positive feedback does not
cause the system to run away because the infinite sum 1+x+x**2+
...+x**n+... is finite for x<1.  In other words amplification
is finite for gain < 1.  Consider for example the simple
feedback system x(n)=s+g*x(n-1) with x(0)=0.  Then x(1)=s, x(2)=
s+g*s, x(3)=s+g*s+(g**2)*s etc.  So in the limit as n -> infinity
x(n) = s*(1+g+g**2+ ...)=s/(1-g) for |g|<1.  This has nothing
to do with nonlinear effects.  Nonlinear effects do explain why
a real system does not actually move to infinity even if the
linear approximation has gain greater than 1.  We know the
climate system has gain < 1 (for small perturbations) as otherwise
the natural system would not have been stable.  This is the
difference between stable and unstable equilibria, for a stable
equilibrium small perturbations die away, for a unstable
equilibrium small perturbations cause the system to runaway.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: PBS, Nova, Frontline Special on Climate
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,sci.geo.meterorology
Message-ID: <20000423.224127.368@yktvmv.watson.ibm.com>
Date: Mon, 24 Apr 2000 02:41:27 GMT
References: <jscanlon-CEC070.20423219042000@news.linex.com>
   <8doq9c$1kk$1@quark.scn.rain.com> <390049A6.165C4F11@math.nwu.edu>
   <20000421.120837.928@yktvmv.watson.ibm.com> <39011795.D2981380@math.nwu.edu>
 
In article <39011795.D2981380@math.nwu.edu>,
 on Fri, 21 Apr 2000 22:08:05 -0500,
 Leonard Evens <len@math.nwu.edu> writes:
 
         <snip>
 
>Thank you for the correction.  I started typing before thinking.
>
>But as you are aware and have pointed out in the past, a one
>dimensional model is bound to be misleading anyway.
 
         I have never said a one dimensional model is bound to be
misleading.  Any model is a simplification of reality and hence
potentially misleading.  This does not mean it is bound to be
misleading.  It means we must be aware of the limitations of the
model.  In fact I have argued in the past that one advantage of
simple models is that their limitations are more obvious.
         In general more complicated systems exhibit a richer variety
of behavior than simpler systems.  So some behavior can not be
explained by simple models because it does not occur in simple
systems.  However this is not true of feedback not running away.
This does occur in simple one dimensional systems and it is not
misleading to use a simple one dimensional model to explain it.
 
>I still wish to make the point that in order to understand what
>happens, one must apply the mathematics appropriate to the
>model.  And the usual mathematics which works for simple feedback
>models may not be very helpful when trying to understand climate
>models.
 
         You should also use a appropriate model.  There is no
good reason to make a model more complicated than it has to be.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: PBS, Nova, Frontline Special on Climate
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,sci.geo.meterorology
Message-ID: <20000425.205624.857@yktvmv.watson.ibm.com>
Date: Wed, 26 Apr 2000 00:56:24 GMT
References: <jscanlon-CEC070.20423219042000@news.linex.com>
   <8doq9c$1kk$1@quark.scn.rain.com> <390049A6.165C4F11@math.nwu.edu>
   <20000421.120837.928@yktvmv.watson.ibm.com> <39011795.D2981380@math.nwu.edu>
   <20000423.224127.368@yktvmv.watson.ibm.com> <39048C29.3040C53E@math.nwu.edu>
 
In article <39048C29.3040C53E@math.nwu.edu>,
 on Mon, 24 Apr 2000 13:02:17 -0500,
 Leonard Evens <len@math.nwu.edu> writes:
 
         <snip>
 
>Your points are well taken.  But I haven't been able to conceptualize
>a proper simple model to help ME understand how the effects of
>water vapor and CO_2 might interact with respect to temperature.
>Your model
>x(n+1) = s + g*x(n)
>does show how, with a coefficient g between 0 and 1, one could
>after an infinite number of repetitions  multiply the
>original perturbation s by  1/(1-g) (and this obtain any
>desired finite positive multiplier for an appropriate g).  This
>is certainly helpful in answering the original question: why
>the multiplier isn't infinite.   There is a slight problem
>in that in this model, n presumably stands for time, and one would
>prefer a formulation in which scaling were not an issue.
>A continous model of the form dx/dt = (log g)(x -b) would
>solve that problem.  But I am still unclear whether the way
>in which the equilibrium value is attained reflects
>what happens in actual climate systems.  Perhaps someone can
>comment on that.
 
         Let s1 be the incoming radiation at the earth's
surface.  Let s2 be the outgoing radiation from the earth's
surface.  Let y be the temperature at the earth's surface.
Let x1 be the atmosphere CO2 concentration, x2 be the H20
concentration.  Assume
 
    (1)       s1 = a * x1 + b * x2
    (2)       s2 = c * y
    (3)       x2 = d * y
    (4)       s1 = s2
 
    (1) accounts for the additional heat radiation back to the earth
by increases in x1 and x2.
    (2) accounts for the the additional heat radiation from the
earth as the surface temperature rises.
    (3) is the postulated dependence of x2 on y (the source of
the water vapor feedback).
    (4) asserts the system is in equilibrium
         Obviously this model contains numerous simplifications.
We are assuming for simplicity that we have scaled so that
all variables are 0 in the initial equilibrium and that
perturbations are small so that the effects are approximately
linear.  Now vary x1, the CO2 concentration, moving the equilibrium
position.  We may solve for the other variables in terms of x1.
In particular
 
    (5)       y = a * x1 / (c - b * d)
                = (a/c) * x1 / ( 1 - b*d/c)
                = (a/c) * x1 * ( 1 + b*d/c + (b*d/c)**2 + ...
 
         So  (a/c) * x1 is the increase in temperature with no
feedback.  This causes x2 to increase further increasing the
temperature (the (a/c) * x1 * b*d/c term).  This further increase
in temperature causes an additional increase in x2 raising the
temperature more (the (a/c) * x1 * (b*d/c)**2) term) etc.  So
we have a geometric series as before and b*d/c best be less than
1 or we are in big trouble.
         Note actually the increase in y from all the terms will
be overlapped rather than occurring sequentially as the above might
suggest.  To model the way y changes we can change (4) to
 
    (6)       dy/dt = e * (s1 - s2)
 
    (6) is asserting the temperature of the earth's surface will
rise when the incoming radiation exceeds the outgoing radiation.
         For simplicity assume the response of x2 to y is very fast
allowing us to leave (3) alone.
         Assume all variables are 0 for t (time) < 0 at which
point x1 becomes some constant value.  Then we may solve for
y(t) as follows.  Substituting (6) becomes
 
    (7)       dy/dt = e * ( a * x1 + b * x2 - c * y)
                    = e * ( a * x1 + b * d * y - c * y)
                    = e * a * x1 + e * (b * d - c) * y
 
         With the initial condition y(0) = 0 the solution of
(7) is
 
    (8)       y(t) = a*x1/(c-b*d) * ( 1 - exp(-e*(c-b*d)*t))
 
         So for b*d < c the system moves to a new equilibrium.
Once again positive feedback need not cause the system to run
away.
                       James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: PBS, Nova, Frontline Special on Climate
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,sci.geo.meterorology
Message-ID: <20000425.223637.674@yktvmv.watson.ibm.com>
Date: Wed, 26 Apr 2000 02:36:37 GMT
References: <jscanlon-CEC070.20423219042000@news.linex.com> 	
   <8doq9c$1kk$1@quark.scn.rain.com> <390049A6.165C4F11@math.nwu.edu> 	
   <20000421.120837.928@yktvmv.watson.ibm.com> <39011795.D2981380@math.nwu.edu>
   <20000423.224127.368@yktvmv.watson.ibm.com> <39048C29.3040C53E@math.nwu.edu>
   <39064231.65DBD80A@dgs.dgsys.com>
 
In article <39064231.65DBD80A@dgs.dgsys.com>,
 on Tue, 25 Apr 2000 21:11:13 -0400,
 Halpern <jbh@dgs.dgsys.com> writes:
>Leonard Evens wrote:
>jbs@watson.ibm.com wrote:
>
>> >> In article <39011795.D2981380@math.nwu.edu>,
>> >    Leonard Evens <len@math.nwu.edu> writes:
>> >          <snip>
>> >> >But as you are aware and have pointed out in the past, a one
>> > >dimensional model is bound to be misleading anyway.>
>
>For one thing, one dimensional models don't inculde the tropics,
>geographical features,  or the poles.  As to photosynthesis, clouds
 
         So what, none of this stuff is necessary to explain the
point at issue namely how a system with positive feedback can
remain stable.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: PBS, Nova, Frontline Special on Climate
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment
Message-ID: <20000502.170450.102@yktvmv.watson.ibm.com>
Date: Tue, 2 May 2000 21:04:50 GMT
References: <jscanlon-CEC070.20423219042000@news.linex.com>
   <8doq9c$1kk$1@quark.scn.rain.com> <390049A6.165C4F11@math.nwu.edu>
   <8dpl1n$j91$1@saltmine.radix.net> <39008D23.C55F4717@math.nwu.edu>
   <8dvuv0$jka$1@newssvr04-int.news.prodigy.com> <8eicpe$qnt$1@quark.scn.rain.com>
   <390CBEF9.642BDE12@math.nwu.edu> <390E90F8.177F9D9C@mic.ericsson.se>
   <390F1BDE.A60AF19@math.nwu.edu>
 
In article <390F1BDE.A60AF19@math.nwu.edu>,
 on Tue, 02 May 2000 13:18:06 -0500,
 Leonard Evens <len@math.nwu.edu> writes:
 
         <snip>
 
>This is all a bit confusing.  The total multiplicative
>effect with Shearer's simple model will always be larger
>than 1.  it is of the form 1/(1-g) where g is what he calls
>the "gain" and is between zero and one.  But if you remember
>the reference, I would like to look at it.
 
         Well actually g can be negative (negative feedback case).
When 0 > g > -1 negative feedback reduces the effect by a factor
1/(1-g).  For g < -1 the system becomes unstable.  This is because
of the lag in the discrete model (and does not occur in the simple
continuous model I also presented).
 
>Of course, one could other explanations of why there is no
>runaway greenhouse effect.   The initial "g" could be greater
>than one, but then non-linear effects could intervene as the
>response grows.
 
         I think this is confused, non-linear effects will stop the
runaway at some point but they won't prevent runaway from occurring.
         A different explanation would be that there are several
feedbacks operating and a system which appears to be unstable if
just one feedback is considered may actually be stable when all the
feedbacks are considered together.
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: PBS, Nova, Frontline Special on Climate
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,sci.geo.meterorology,sci.environment
Message-ID: <20000506.181725.969@yktvmv.watson.ibm.com>
Date: Sat, 6 May 2000 22:17:25 GMT
References: <jscanlon-CEC070.20423219042000@news.linex.com>
   <8doq9c$1kk$1@quark.scn.rain.com> <390049A6.165C4F11@math.nwu.edu>
   <8et195$h1q$2@quark.scn.rain.com> <39144E29.167B2C09@math.nwu.edu>
 
In article <39144E29.167B2C09@math.nwu.edu>,
 on Sat, 06 May 2000 11:54:01 -0500,
 Leonard Evens <len@math.nwu.edu> writes:
 
         <snip>
 
>Still all you can go on is public statements.  You have to
>assume that politicians will at least try to do what they
>say they will do.  So just as we should all assume that
>George W will try to abolish abortion, since he has said
>that is his goal, we should also assume Al Gore would try
>to do what he can about climate change, since he says that
>is what he will do.
 
         An interesting analogy, but not one which would encourage
me to believe Gore is likely to do anything effective about climate
change.  Btw wasn't Gore antiabortion himself at one time?
                        James B. Shearer
=========================================================================
Path: yktvmv!jbs
Subject: Re: PBS, Nova, Frontline Special on Climate
From: jbs@watson.ibm.com
Organization: IBM
Newsgroups: sci.environment,sci.geo.meterorology,sci.environment
Message-ID: <20000507.171429.458@yktvmv.watson.ibm.com>
Date: Sun, 7 May 2000 21:14:29 GMT
References: <jscanlon-CEC070.20423219042000@news.linex.com>
   <8doq9c$1kk$1@quark.scn.rain.com> <390049A6.165C4F11@math.nwu.edu>
   <8et195$h1q$2@quark.scn.rain.com> <39144E29.167B2C09@math.nwu.edu>
   <20000506.181725.969@yktvmv.watson.ibm.com> <3914D847.C762AB02@math.nwu.edu>
 
In article <3914D847.C762AB02@math.nwu.edu>,
 on Sat, 06 May 2000 21:43:19 -0500,
 Leonard Evens <len@math.nwu.edu> writes:
 
         <snip>
 
>If one is concerned with climate change as an important issue, and
>if one thinks we should start at least minimal efforts now,
>then there is no question about which of the major party candidates
>is more likely to do something about it.  If you are not such
>a person, then you probably want to vote for Bush because he
>won't do any such things.  So why bother questioning Gore's
>commitment?
 
         It is true that the degree of Gore's commitment is not of
great concern to me.  However it seemed to me that comparing it to
positions (on abortion) of G. W. Bush which are widely seen as
insincere was faint praise indeed.
         As for who is more likely to do something about climate
change you must also consider who would be better positioned
politically to do something.  There is a plausible theory that the
easiest way for politicians to accomplish som