HDTenEightyP/NetNews huggingface dataset:
From: paul@mtnmath.UUCP (Paul Budnik)
Newsgroups: sci.physics
Subject: Re: Lowneheim-Skolem theorem (was: Continuos vs. discrete models)
Date: 18 Nov 92 15:34:47 GMT
Organization: Mountain Math Software, P. O. Box 2124, Saratoga. CA 95070

In article <TORKEL.92Nov18114047@isis.sics.se>, torkel@sics.se (Torkel Franzen) writes:
> In article <1992Nov17.124233.24312@oracorp.com> daryl@oracorp.com 
> (Daryl McCullough) writes:
>    >LS shows that there can
>    >never be a demonstration that space-time must be continuous, because
>    >there is no property of an uncountable set that doesn't also hold of
>    >some countable set.
>   Here is a counterexample to your assertion: an uncountable set has
> the property of being uncountable, whereas no countable set has this
> property.

This would be a valid argument if uncountable had an absolute definition.
I think uncountable is only meaningful relative to some formal system. There
are plenty of examples of sets uncountable in one system that are countable
in stronger systems. The question of whether uncountable has an absolute
definition is a philisophical one that I expect we have different opinions on.

Paul Budnik.
Newsgroups: sci.physics,sci.math
From: jim@cs.UAlberta.CA (Jim Easton)
Subject: Re: Three-sided coin
Organization: University of Alberta, Edmonton, Canada
Date: Tue, 24 Nov 1992 01:16:12 GMT


This is in reply to an article posted by Blair  Houghton of
Intel Corp., Chandler, Arizona, a while back.

> In article <jim.721702281@st-michael> jim@cs.UAlberta.CA (Jim Easton) writes:

> >Given that it is possible to bounce from one state to another it
> >is more probable to bounce out of a high energy state to a lower
> >energy state than it is the reverse.  I claim that the lowest energy
> >state is the most probable and therefore conclude that the three states
> >should be equal in energy.
> 
> This is fallacious.
> 
> Imagine a three-sided "coin" made by bending a very thin
> sheet (of something very low-density like titanium) in the
> middle at about a 170-degree angle, then adding a thick
> bead of gold or lead inside the crease.  The low-energy
> states of this object are the two states that occur when
> the coin lands with the convex side down (resting flat on
> one leaf or the other).  The high-energy state occurs when
> the coin lands with the concave side down (like a tent).
> 
> The concave and convex sides have nearly the same
> probabilities, but there are two states on the convex side,
 
It is here that I disagree - if you gave this thing a fair
toss it would almost never land with the pointy side up.

> which splits the probability there; say it's something like
> 30, 30, 40 for convex/A, convex/B, and concave, respectively.
> 
> This is a direct contradiction of the idea that "the lowest
> energy state is the most probable."
> 
It  would be if your estimate of the probabities are anywhere
near right but I think they're not.  Have you ever heard of
loaded dice.  They are dice that have a BB embedded in one side
and the probability that the opposite side comes up more often
is greatly enhanced - by far more than is required to overcome
the natural advantage to the house in a game of crap.  In fact
the professional cheaters don't bother with loaded dice they
are too easy to spot - they just round some of the edges just
a very little bit, not enough for the average naive mark to
notice and it's enough.

I was an experimentalist before I came to work here and I
am a great believer in experiment to settle such issues.  I
think you should make your beasty and see how often the pointy
side will come up if given a "fair toss".

So what is a "fair toss"?  Well if you throw it from a cup 
onto a table from a height several times larger than the size
of the die I would call that a fair toss.  I'd bet you a fair
large sum that out of a hundred throws it doesn't land pointy
side up even once.

Maybe someone could address the following question;  How often
would you have to throw it to get a fair estimate of the
probabilities.

	Jim
Organization: Doctoral student, Physics, Carnegie Mellon, Pittsburgh, PA
Newsgroups: sci.physics
Date: Fri, 20 Nov 1992 14:17:26 -0500 
From: Steven Timm <st0o+@andrew.cmu.edu>
Subject: Re: Flying fast enough and becoming a black hole
Distribution: sci.physics

The idea of increasing mass with increasing velocity is one of the more 
common fallacies.  Consider the following:  There are some quasars in the
universe whose redshifts indicate they are moving away from us at .99c
due to the expansion of the universe.  It follows that earth, and the solar
system, and the local galaxy, are going .99c in their rest frame.

Since our mass must be the same in our reference frame or theirs, and we've
not turned into a black hole in either case, it follows that we are not 
in danger of turning into a black hole through excess velocity.

The actual process of making a black hole involves general relativity
with which I am not too familiar, but I think it's clear that speed alone
will not do it.

Steve Timm

Newsgroups: sci.physics
From: jtbell@hubcap.clemson.edu (Jon Bell)
Subject: Re: energy, mass, and all that
Organization: Presbyterian College, Clinton SC
Date: Sun, 22 Nov 1992 21:40:37 GMT

In article <98706@netnews.upenn.edu> weemba@sagi.wistar.upenn.edu (Matthew P Wiener) writes:

>In 1905, Einstein pointed out that there is an inertia associated with
>energy.  T=E/c^2.  (Not E=mc^2.)  That meant that if you had two equal
>systems vis-a-vis their _matter_, they would weigh differently if the
>one was at a higher temperature than the other.

Just out of curiosity, has anyone actually _observed_ the increased mass
(or weight) of a hot object?  (I'm not disputing Matthew's statement, just
wondering if there is any direct experimental evidence for it.)

Jon Bell / Dept. of Physics & Comp. Sci. / Presbyterian College / Clinton SC
From: ucap22w@ucl.ac.uk (Martin S T Watts)
Newsgroups: sci.physics
Subject: Re: TIME HAS INERTIA (reply to Scott Chase)
Date: 16 Nov 92 10:56:02 GMT
Organization: Bloomsbury Computing Consortium

sichase@csa1.lbl.gov (SCOTT I CHASE) writes:

>In article <1992Nov12.201646.31516@bas-a.bcc.ac.uk>, ucap22w@ucl.ac.uk (Martin S T Watts) writes...
>>sichase@csa1.lbl.gov (SCOTT I CHASE) writes:
>>>In article <1992Nov09.192052.25358@bas-a.bcc.ac.uk>, ucap22w@ucl.ac.uk (Martin S T Watts) writes...

>>(And if you think that, say, positron-electron annihilation is an example of
>>the destruction of mass, then think again.)

>Sure.  What would *you* call it?  Where do *you* think the mass goes?

I can see you've sweated blood over this problem. Maybe since the products
of e+ e- annihilation are two or three gamma ray photons, the mass of the
pair becomes the mass of the photons. Does that seem unreasonable?

>>It wouldn't surprise me if American Universities were turfing out copies of
>>J. Phys. A! I only included the reference in case people doubted the
>>authenticity of my claim - I hadn't thought people would go to the trouble
>>of looking it up. 

>The purpose of providing a reference is to allow the reader to find details
>that you have omitted for brevity or clarity.  References are not generally
>provided, as you seem to think, merely to look professional.  

Well, I never knew that - thank you for explaining. :-)

>In and of 
>themselves, they provide no authentication of a claim.  

My claim was that Bondi had said "Energy has mass" and that energy and mass
are not interconvertible. My reference provides authentication of that claim.
It's hardly my fault if the University of California, or wherever, chucks
out its copies of Physics Bulletin to preserve valuable space for toilet paper.

>You are welcome
>to explain to us, if you care, what Bondi had to say.

On an international public access bulletin board that's very magnanimous, I
must say.

>  If not, then how
>are we supposed to proceed with this discussion?

For a start, have you looked up the other references I gave? If not, perhaps
*you* could explain to us, in the mean time, where the mass of the positron-
electron pair goes in annihilation. I'd be interested in proceeding with this
discussion and willing to go into more detail, by all means, but at the 
moment your tone seems a little too aggressive to be conducive. If you are
genuinely interested, please say so, and also say what your understanding of
the subject is, so I can put you straight more easily.

Martin Watts.
Newsgroups: sci.physics,alt.sci.physics.new-theories,sci.optics
From: sarfatti@well.sf.ca.us (Jack Sarfatti)
Subject: re: John Baez's remarks on parallel slit kets vs. perpendicular slit kets in standard quantum optics.
Organization: Whole Earth 'Lectronic Link
Date: Mon, 23 Nov 1992 02:57:59 GMT


Well John Baez you don't like "super"? How about superposition?
superstring? superfluid? superconductivity? superstition? supercilious?

Are you saying that Princeton University supports crackpot science in their
PEAR laboratory headed by Dean of Engineering, Robert Jahn with money from
Mc Donnell Douglas and Federal Intelligence Community?

But what about the substantive issue. Parallel slit kets seem to work as
well as perpendicular ones. If not, why not?

Linearity seems to contradict local dynamics. Thus, a polarizing beam
splitter makes two beams with no common support in space, so that

|i> = |e+><e+|i> + |o-><o-|i>

and for some times t, at least, when <x|e+> not zero then <x|o-> is zero
and vice versa. There is no x such that both <x|e+> and <x|o-> are non-
zero.

A half-wave plate (1/2) acts on o-beam. It acts locally. There is no way it
can affect the separated e-beam. The plate is represented by a unitary
operator U(1/2) in the Hilbert sub-space in which |e+> and |o-> form an
orthonormal basis. <e+|o-> = 0 etc.  The locality of the photon-electron
scattering in region of 1/2-plate means

U(1/2)|o-> = |o+>

for the time being, let's agree with Ramsay that <e+|o+> = 0 . There is
still a paradox.

Local dynamics demands that

U(1/2)|i> = |e+><e+|i> + U(1/2)|o-><o-|i> = |e+><e+|i> + |o+><o-|i>

Linearity demands the contradictory

U(1/2)|i> = U(1/2)|e+><e+|i> + U(1/2)|o-><o-|i> = |e-><e+|i> + |o+><o-|i>

but we would be surprised if by putting a 1/2 plate in the o-beam we also
rotated the plane of polarization of the far away e-beam by 90 degrees.
This would be a new kind of dynamical nonlocality different from
kinematical connection nonlocality tested by Bell's inequality.
From: matt@physics.berkeley.edu (Matt Austern)
Newsgroups: sci.physics
Subject: Re: Abian and the Fundamental Theorem o
Date: 22 Nov 92 13:25:10
Organization: Lawrence Berkeley Laboratory (Theoretical Physics Group)
	<mcirvin.722460851@husc8>
Reply-To: matt@physics.berkeley.edu
NNTP-Posting-Host: physics.berkeley.edu
In-reply-to: mcirvin@husc8.harvard.edu's message of 22 Nov 92 19:34:11 GMT

In article <mcirvin.722460851@husc8> mcirvin@husc8.harvard.edu (Mcirvin) writes:

> "If space and time can be transformed into each other by a change of 
> reference frame, why is it that there are three spatial dimensions but
> only one temporal one?"

[Description of Minkowski space deleted]

> Why?  Nobody knows.  But that's the model that seems to correspond
> to reality, and it's mathematically consistent. 

I agree with the summary "nobody knows," but I should mention that
some people are trying to figure out the answer---that is, trying to
understand why there are four dimensions of which three are spatial
and one is temporal.

The string folks say that really there are many more than four
dimensions, but that most of them are "compactified," i.e., curled up
into little circles.  The question of why there are four dimensions
and why they have the properties that they do, then, comes down to why
the underlying geometry compactified the way that it did.  This
question is a topic of current investigation.

This is not to be taken as an endorsement of string theory; all of
this work may be wrong, or maybe "not even wrong."  Still, I think
it's interesting that it is now beginning to be possible to ask this
question mathematically, even if the answer is still eluding us.
--
Matthew Austern                   Just keep yelling until you attract a
(510) 644-2618                    crowd, then a constituency, a movement, a
austern@lbl.bitnet                faction, an army!  If you don't have any
matt@physics.berkeley.edu         solutions, become a part of the problem!
Xref: sparky sci.physics:19165 sci.astro:12151
From: Richard.Mathews@West.Sun.COM (Richard M. Mathews)
Newsgroups: sci.physics,sci.astro
Subject: Re: Higgs Spotted?
Date: 16 Nov 92 22:29:34 GMT
Organization: Sunsoft Inc., Los Angeles, CA.
NNTP-Posting-Host: astro
Originator: richard@astro.West.Sun.COM

crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:

>     Feel free to give us the 'more complete' quote.

I did.  The originally posted quote preceded by the sentence I mentioned
in my last post is the complete quote that I have.

>      Colloquial politician definition of canals as 'things that used
>      to hold water'.

Is that like a colloquial politician's definition of "I am not a crook"
or "no new taxes"?  The definition of canal *is* an artificial waterway.
Only by redefining words can you say that Quayle's statement was accurate.
By that standard, any statement can be proven true.

>>In Quayle's statement, we can either take "oxygen" to mean atomic oxygen
>>or molecular oxygen....
>>Either way, Quayle loses (but he took care of that
>>2 weeks ago anyway).

>     Only if you assume that he was talking about breathing water.
>     He was fully aware of proposals to procure consumables from 
>     Mars itself.

No, I am not assuming he was talking about breathing water.  His statement
indicated that the presence of water meant you would be able to breathe.
My claim is you need water plus quite a bit of energy and equipment.  You
may say his statement was a mere oversimplification.  I consider such a
severe oversimplification to be a factual error.  And do we want such
"simple minded" (sorry about the pun) leaders?

     Richard M. Mathews			F oster 
					 E stonian-Latvian-Lithuanian
Richard.Mathews@West.Sun.COM		  I ndependence and
					   F reedom!
Newsgroups: sci.physics
From: palmer@sfu.ca (Leigh Palmer)
Subject: Re: Electric Power Transmission
Organization: Simon Fraser University
Date: Fri, 20 Nov 1992 19:09:45 GMT

In article <HAGERMAN.92Nov19204019@rx7.ece.cmu.edu> hagerman@ece.cmu.edu (John
Hagerman) writes:
>In article <1992Nov19.202817.29139@sfu.ca> palmer@sfu.ca (Leigh Palmer)
writes:
>>
>> Wow. Thanks for the information, John. I hope someone will be able
>> to drop the other shoe and tell us where to learn more about this
>> twenty-year-old technology.
>
>Your ability to communicate sarcasm without a smiley is nice to see.
>But I fear that your comments may mask one important point of my post,
>which was to demonstrate that many of the questions asked here can be
>sufficiently answered by a tiny bit of research.  Need I explain why
>actually doing such research is useful?

I've failed again, I'm afraid. I wasn't being sarcastic; I have no idea
how this is done, and since I teach physics, I think that is a lacuna
in my knowledge which needs to be filled. I asked some specific 
questions about generation and distribution, and I'd really like to
know the answers to those questions.

I've only recently adopted the "smiley" (my version has a double chin)
because I was being misunderstood. I am quite vain about my command of
the language, and I had never seen a smiley in Mark Twain, so I didn't
use them, either. Now I see that it can work the other way as well. 

Leigh
Newsgroups: sci.physics
From: pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt)
Subject: Re: TIME HAS INERTIA.   Att:  PRATT  FUND. THM. OF ALGEBRA 
Organization: Computer Science Department,  Stanford University.
Date: Mon, 23 Nov 1992 01:14:07 GMT

In article <1992Nov22.214312.13337@oracorp.com> daryl@oracorp.com (Daryl McCullough) writes:
>What I think is the tricky part of Abian's proof is the assumption
>that just because a function has an essential singularity at z = 0,
>then it can't be well-defined in the limit z -> 0. Just because the
>expansion of 1/(kz^n + ...+ bz + a) has an infinite number of negative
>powers of z, why does it follow that the limit of the function as
>z -> 0 cannot be 1/a?

My point exactly.

>It actually is true that if a function f(z) has an expansion with an
>infinite number of negative powers of z that is valid near z = 0, then
>the limit of f(z) as z -> 0 is undefined (it doesn't have a value
>which is independent of the way the limit is taken).

While brushing up on this stuff I ran across a mind-boggling theorem
about this situation (the case of an essential singularity) due to
Emile Picard in 1879.  In *any* neighborhood of an essential
singularity, f takes on every possible value, with one exception,
infinitely often!

>However, the
>proof of this fact may very well require something as powerful as the
>Fundamental Theorem of Algebra. Professor Abian, could you tell us a
>simple proof that a power series with an infinite number of negative
>powers of z cannot have a limit as z -> 0?

Hear, hear.

I think instead of talking about singularities he should appeal to the
uniqueness of the series in its domain of validity.  He has argued
that, under the hypothesis of no zeroes in the denominator, two
distinct series would share a domain of validity.  This should suffice
for a contradiction.

In article <31415926535Nov22.2718281> (Abian) writes
>Several people's reaction was that my proof is  "a load of crap",
>"utter bullshit" (they even did not use the polite form "beta-sigma",
>invented by me!) and that I am  "a crackpot".
>Among the above people are:  V. R. PRATT of Stanford University and P.Da COSTA.

I deny the lot.  Where did I say even one of these things?  (I did call
Newton a crackpot and you are entitled to your inference, but that's
not the same thing as calling you a crackpot.)

>Otherwise, this is the last time you are hearing from me concerning FTA.

It was good while it lasted, your thought-provoking correspondence has
been most appreciated.
-- 
Vaughan Pratt	  		A fallacy is worth a thousand steps.
Newsgroups: sci.physics
From: abbasi@star.enet.dec.com (My name is Nasser Abbasi)
Subject: Question on the energy of EM field , why the missing term in Feynman book?
Organization: Digital Equipment Corporation
Date: Tue, 17 Nov 1992 09:01:34 GMT


Hi,

 Iam looking at "the Feynman lectures on physics" VOL 2, page 27-5
 equation 27.13

 this relates to an EM field energy.

 he said that the rate of doing work by the EM field on a unit matter , which
 is E.J is equal to 
                     - DIV S - du/dt

where S is the Poynting vector (power leaving region), and du/dt is the
rate of change of the energy density of the field inside the region.

this is all fine, but my question is on E.J part (ie. the left hand side
of the question).

why did he not also add the H.M term to E.J ?  H.M is the rate of work done by 
the magnetic field component on the "magnetic current". (H is the magnetic
field intensity, and M is the magnetic current density, J is the current
density, E is the electric field intensity).

he only considered the power done by the electromotive part of the field (E),
and did not look at the power done by magnomotive (sp?) part?

I looked at "Time-Harmonics Electromagnetic fields" by Roger F. Harrington,
page 11, equation 1-38, and there, Harrington does show the power due to
the magnetic part as well as the electric part as the sources for the power
of the EM field.

can some also please give a short word or a pointer on how to best look at 
the power supplied by magnetic field (i.e. H.M) I find this one harder, it is 
easy to see the power supplied the Electric filed (E.J) but not the (H.M). 

than you,
/nasser


Newsgroups: sci.physics
From: terry@aslws01.asl.dl.nec.com (Terry Bollinger)
Subject: Auto-Deletes of Postings by Name/Phrase
Organization: NEC America, Inc Irving TX
Date: Fri, 20 Nov 1992 15:37:22 GMT

Hi folks,

Since there are a lot of different threads and authors on this group,
I thought I'd mention that if you use "rn", you can do very broad
auto-deletes that will ensure that you can keep the focus on what
*you* want to talk about.

You do it by explicitly editing (Ctrl-K) your kill file to broaden the
scope of the kills.  Some quick examples (ignore my indenting):

    /bollinger/aj

... kills all letters that even *mention* my last name, whether in any of
the header lines, or in the text itself.  This command is indifferent
to case, so it will nail emails containing Bollinger, BOLLINGER, bollinger,
whatever.  You can use entries of this type to ensure that you will never
even see a particular name or concept even mentioned again on your custom
set of threads.

If you wish to be a little more precise you can use:

    /^from: .*terry/aj

...which would nail only emails sent from my (or whoever's) email name.
This is what you might want if you don't chafe too much at simply seeing
someone mentioned, but do not wish to receive any of their postings.

It doesn't have to be just the "from:" field; you can eliminate by using
some other header field name.  For example:

    /^newsgroups: .*bizarre/aj

...ensures that any posting cross-referenced to any group containing the
name "bizarre" will be kept out of your thread subset.

In fact, if you disdain ALL forms of cross-posting, you can restrict your
subset to postings that do not have *any* cross-references by looking for
the comma that separates more than one group:

    /^newsgroups: .*,/aj

Finally, you may want a list of generic "don't let me see subjects with
these words in them" entries.  (If you are only basing your kills on
subject lines, you only need "j" at the end instead of "aj".)

    /astrol/j
    /crackpot/j
    /joke/j
    /psychic/j
    /ufo/j

Remember that these will kill *any* occurrence of the letter sequence you
give, whether upper, lower, or mixed case.  So be careful -- a very short
string is liable to find words you did not intend to get.  (You can ensure
an exact word (vs. part of a word) by using "\b" before and after the word,
as in "/\bufo\b/j" )

Because this group is so large and diverse, you have a right to read as
much or as little of it as you wish.  Commands such as the above will,
at least for "rn" users, help provide defacto subgrouping more along the
lines of whatever your interests may be.

				Cheers,
				Terry Bollinger