HDTenEightyP/NetNews huggingface dataset:
From: matmcinn@nuscc.nus.sg (Brett McInnes)
Subject: Re: TIME HAS INERTIA - improved version
Organization: National University of Singapore
Date: Thu, 12 Nov 1992 09:07:09 GMT

jbaez@riesz.mit.edu (John C. Baez) writes:
: 
: and identifying m with m(0) and applying Einstein's equation we realize
: Scott Chase' dream - a theory that calculates the speed of light:
: 
: 			 c = 1
: 
: Whew, I think I can go home now and feel like I've accomplished something.

No.       c=1 [Baez] must be replaced by c=-1 [Abian
D
	.
From: abond@rvgs.vak12ed.edu (Andrew H. Bond)
Subject: Re: teacher needs email ideas for students
Organization: Virginia's Public Education Network (Roanoke)
Date: Mon, 09 Nov 92 03:53:12 GMT

	I would suggest that you compile a list of available
mailing lists that your students can choose from. If you don't
know what a mailing list is, I'll explain.
	A mailing list is kind of like a computer newsletter,
also alot like USENET newsgroups, only they take place through
email channels. The way it works is: Everyone on the list has
the ability to mail messages to a central address, the list
administrator(sometimes just a computer program for passively
moderated lists) collects all the messages and mails them out
to everyone on the list. In my travels through the network
recall coming across a text file containing the names,
addresses, and purposes of mailing lists(I think there were
about a thousand). If I get some free time I will see if I can
locate it for you. maybe someone who reads this will know the
name & loc of such a list.
-- 
andrew h bond, 	rvgs	
Newsgroups: sci.physics,sci.space,alt.conspiracy
From: ledwards@leland.Stanford.EDU (Laurence James Edwards)
Subject: Re: NASA Coverup
Organization: DSG, Stanford University, CA 94305, USA
Date: Thu, 5 Nov 92 03:57:26 GMT

In article <1992Nov4.203722.6838@engage.pko.dec.com>, moroney@ramblr.enet.dec.com writes:
|> [....]
|> As to jumping in spacesuits on the moon, don't forget that those suits are
|> probably rather stiff.  Probably the jumps are quite poor compared to what
|> would be possible if they wore normal clothing with lead-filled backpacks
|> with the same mass as the suits.
|> 
|> -Mike

self preservation may also be involved here ... if you take a giant leap
and fall on something sharp that punctures your spacesuit ...

by the way, this is all one long running joke, right?

Larry Edwards
Newsgroups: sci.physics
From: sschaff@roc.SLAC.Stanford.EDU (Stephen F. Schaffner)
Subject: Re: teacher needs email ideas for students
Organization: Stanford Linear Accelerator Center
Date: Mon, 9 Nov 1992 19:51:54 GMT

In article <1992Nov09.035312.6820@rvgs.vak12ed.edu>, abond@rvgs.vak12ed.edu (Andrew H. Bond) writes:
|> 	I would suggest that you compile a list of available
|> mailing lists that your students can choose from. If you don't
|> know what a mailing list is, I'll explain.
[...]

|> In my travels through the network
|> recall coming across a text file containing the names,
|> addresses, and purposes of mailing lists(I think there were
|> about a thousand). If I get some free time I will see if I can
|> locate it for you. maybe someone who reads this will know the
|> name & loc of such a list.
|> -- 

I've seen a couple of them available by anonymous ftp.  There's one at 
Dartmouth: ftp to DARTCMS1.DARTMOUT.EDU, change directory to "siglists", and 
get the file "internet.lists" (it contains both internet and bitnet lists, 
giving the internet name by default in case of overlap; there's another 
version of the file giving bitnet addresses by default).  There's another 
list at ftp node 192.33.33.22 (I forget where it is), in netinfo/interest-groups.
Both lists are long.

-- 
Steve Schaffner        sschaff@unixhub.slac.stanford.edu
	The opinions expressed may be mine, and may not be those of SLAC, 
Stanford University, or the DOE.
From: andrew@rentec.com (Andrew Mullhaupt)
Newsgroups: sci.physics
Subject: Re: Einstein and Judaism
Date: 11 Nov 92 16:37:33 GMT
Organization: Renaissance Technologies Corp., Setauket, NY.

In article <TORKEL.92Nov10095811@isis.sics.se> torkel@sics.se (Torkel Franzen) writes:
>In article <1992Nov9.232752.24615@asl.dl.nec.com> terry@asl.dl.nec.com writes:

>   Here are some relevant passages from Pais:
>
>   During the last twenty-five years of life, Einstein maintained that
>   quantum mechanics was incomplete. He no longer believed that quantum
>   mechanics was wrong but did believe that the common view of the physics
>   community was wrong in ascribing to the postulates of quantum mechanics
>   a degree of finality that he held to be naive and unjustified. ...

This is a question on which a single source of information is not such
a good idea. Reference is made to Einstein's later beliefs by Wheeler
Prigogine, and others which are not entirely consistent with this statement
of Pais.

Torkel and I already duked this one out in sci.philosophy.meta, so I
won't get into the details. Popular expositions which bear on the
question include Prigogine's _Time: From Being to Becoming_ and the
sequel to Hawking's _Brief History of Time_ (i.e. companion volume to the
movie).


Later,
Andrew Mullhaupt
Newsgroups: sci.physics
From: sarfatti@well.sf.ca.us (Jack Sarfatti)
Subject: PS Isham 3 meaning of global boundary conditions in QM FTL
Organization: Whole Earth 'Lectronic Link
Date: Sun, 8 Nov 1992 02:59:29 GMT


Look at Isham's last eq. (6.2.8) on conditional probability. Let A be for
transmitter and B represent receiver in quantum connection communication
gedankenexperiment.  Part of the global boundary conditions in region A that
influence B is the range a of A.  That range is an objective feature of the
experimental arrangement, for example, whether there are two transmitter
counters, one for each beam from calcite, or only one capturing each beam
with almost 100% probability.  In latter case, the nonlocal conditional
probability is also identical to the local receiver probability because
there is nothing else at A left to trace over.  This is a vital point that
Ramsay does not see. It leads him to falsely claim that one must compare
data at both ends - yes in Aspect's experiment, no in mine.
From: jac@ds8.scri.fsu.edu (Jim Carr)
Newsgroups: sci.physics
Subject: Re: NASA Coverup
Date: 9 Nov 92 21:12:19 GMT
Reply-To: jac@ds8.scri.fsu.edu (Jim Carr)
Organization: SCRI, Florida State University

In article <1992Nov9.172600.17151@sei.cmu.edu> firth@sei.cmu.edu (Robert Firth) writes:
>
>Nope: you can deduce the mass of the moon from the magnitude of the
>ocean tides.
>
>[I Newton: Philosophiae naturalis principia mathematica,
> Book III, Prop XXXVII, Problem XVIII]

Is such an estimate really all that accurate?  I have always discounted 
it since the height (not to mention the timing) of tides depend to such 
a large extent on local conditions.  Is this method accurate to a factor 
of 2 given the calculational tools in Newton's day?  

--
J. A. Carr                                    |  "The New Frontier of which I  
jac@gw.scri.fsu.edu                           |  speak is not a set of promises
Florida State University  B-186               |  -- it is a set of challenges."
Supercomputer Computations Research Institute |   John F. Kennedy (15 July 60)
Newsgroups: sci.physics
From: ddixon@nyx.cs.du.edu (David Dixon)
Subject: Online Literature Search
Organization: Nyx, Public Access Unix @ U. of Denver Math/CS dept.
Date: Mon, 9 Nov 92 17:25:15 GMT

I am really tired of leafing through Chem. Abstracts.  I know that there
are online literature search services available.  In fact, our library
has access, but it would cost me each time I use it.  Is it possible
to get Chem. Abstracts (or similar) on CD-ROM?  Are there publically
accessible services that perhaps cover specific areas rather than the
whole of science?  Thanks.

					Dave
Newsgroups: sci.physics
From: pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt)
Subject: Re: Some physics questions
Organization: Computer Science Department,  Stanford University.
Distribution: na
Date: Sun, 8 Nov 1992 17:46:08 GMT

In article <1dhv1tINNrnh@iskut.ucs.ubc.ca> ramsay@unixg.ubc.ca (Keith Ramsay) writes:
>For example, if I ask how long tall you are, the proposal is that the
>only content which can be gathered from the question is to compare
>your height to some reference length(s). A "length" is, essentially,
>just defined by its ratios to the framework of all the other lengths
>which we can talk about-- most especially to standardized ones. But,
>if, for example, some bizarre change were to occur which affected only
>the particular phenomenon which was used to define the standard,
>leaving the ratios of most other quantities basically intact, then
>we'd surely agree to change the standard, rather than regard all the
>other quantities as having changed. (The old example was, "what if the
>platinum bar in Paris were stretched".)

What would happen if that platinum bar and a 9192631770 Hz cesium clock
were transported to some other local group of galaxies, keeping it at
the prevailing outside temperature of 2.7K?  After one third of the
trip would one see exactly the same number of clock cycles along the
length of the bar as after two thirds?  (The trip will be quite long
enough for the bar to reach thermal equilibrium.)

Light is supposed to zip along an honest meter bar in exactly
1/299792458 seconds (the bar in Paris may need an extension welded on
to make it honest at 2.7K).  Hence the above measurement should be
*exactly* 656616555/21413747 clock cycles, in round numbers about
30.6633189884983697621906152155435477966560 (more digits on demand :-),
Could this conceivably become exactly 30.6634 or 30.6632 at some point
during the trip?

With regard to bar length, assume you were carrying a variety of meter
bars of different stable materials (I have no idea what materials are
sufficiently stable for billions of years).  With regard to clock
frequency, assume you were carrying a variety of atomic clocks based on
hyperfine transitions of various elements.  And assume that the
observed change was the same to within 10% of the change for all
combinations of bars and clocks.

Given these circumstances, which parameter would you prefer to say had
changed, light speed, bar length, or clock frequency?  Or would you
prefer to say that there was no basis for choosing among these?
-- 
Vaughan Pratt
From: matt@physics2.berkeley.edu (Matt Austern)
Newsgroups: sci.physics
Subject: Re: No big crunch?
Date: 5 Nov 92 10:18:39
Organization: Lawrence Berkeley Laboratory (Theoretical Physics Group)
	<1d9lptINN94@agate.berkeley.edu>
	<Nov.4.20.34.21.1992.1961@ruhets.rutgers.edu>
	<1992Nov5.022306.25731@murdoch.acc.Virginia.EDU>
Reply-To: matt@physics.berkeley.edu
NNTP-Posting-Host: physics2.berkeley.edu
In-reply-to: crb7q@kelvin.seas.Virginia.EDU's message of Thu, 5 Nov 1992 02:23:06 GMT

In article <1992Nov5.022306.25731@murdoch.acc.Virginia.EDU> crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:

>      In turn, I am much more sympathetic to baryonic dark matter if
>      it can be made to work.  However, we seemed to be talking about
>      'pixie' matter, a quantity that can probably be invented to 
>      explain anything.   About 'fixing up' omega, I am not sympathetic
>      at all.  There seems to be no compelling need from my perspective
>      to have omega be one.

I agree that it's a bit dogmatic to insist that omega be exactly 1; it
seems to me a bit like inventing a problem and then triumphantly
proclaiming that you have a solution.  (And my understanding is that
the folks who work on inflation now agree that omega need not be
exactly 1.)

However, I don't really think that nonbaryonic dark matter is so
unnatural an idea.  Again: most extensions of the Standard Model
predict something or other that could be nonbaryonic dark matter.  Any
one of these possibilities sounds a bit bizarre and fanciful, but this
prediction is so very generic that it doesn't seem too absurd that
*something* or this sort exists.  Nobody believes that the Standard
Model is the full story, so why should it be so surprising if maybe
some of the new non-Standard Model physics is cosmologically
important?

Of course, I'm not suggesting that anyone be so gullible as to believe
everything that particle theorists tell them.  I just think that this
explanation is plausible enough so that we should try to do
experiments to test it.
--
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!
From: matt@physics.berkeley.edu (Matt Austern)
Newsgroups: sci.physics
Subject: Re: NEWS: Galileo Cleared of Heresy Charges by Vatican
Date: 8 Nov 92 11:11:38
Organization: Lawrence Berkeley Laboratory (Theoretical Physics Group)
	<1992Nov7.163126.20553@murdoch.acc.Virginia.EDU>
	<1dhvm2INN6e5@gap.caltech.edu>
Reply-To: matt@physics.berkeley.edu
NNTP-Posting-Host: physics.berkeley.edu
In-reply-to: brahm@cco.caltech.edu's message of 8 Nov 1992 02:57:06 GMT

In article <1dhvm2INN6e5@gap.caltech.edu> brahm@cco.caltech.edu (David E. Brahm) writes:

> For the universe, one can consider a sum of "histories," which are 4D
> manifolds with metrics (modulo diffeomorphisms).  Hartle and Hawking
> proposed very simple boundary conditions, restrictions on the histories
> analogous to restricting the baseball to start at the pitcher and ending at
> the catcher: "This class consisted of curved spaces, without singularities,
> and which were of finite size, but which did not have boundaries or edges."
> This is called the "No Boundary" proposal.
> 
> Once again, the sum over all histories is dominated by a small subset, and
> the task of quantum cosmology is to show that this dominant path is in fact
> the 4D macroscopic universe we call home.

Um, not to get offensive about this, but...

Even ordinary path integrals make me a bit nervous sometimes; I
occasionally have trouble keeping myself under control so that I don't
jump up, screaming "What's the measure?"  I can usually manage to do
this by telling myself comforting lies about how the path integral is
really the limit of a well-defined integral on a lattice as the
lattice spacing is taken to zero, and by ignoring the fact that the
measure diverges in this limit.

I have even more trouble, though, when people talk about doing path
integrals in quantum cosmology.  It doesn't seem at all clear to me
that there is any sensible measure for an integral over the space of
all possible four-dimensional manifolds.
--
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!
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: GR with no Einstein? (Was: Re: No big crunch?)
Organization: MIT Department of Mathematics, Cambridge, MA
Date: Fri, 6 Nov 92 23:24:35 GMT

In article <1992Nov6.042306.899@murdoch.acc.Virginia.EDU> crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:

>     Suppose, as I have been, that you *don't even have* GR.
>     In 1906, there was no certainty that GR would be developed.
>     In fact, if Einstein had died in 1906, I'm quite sure it 
>     wouldn't have been.

Oh good, let's argue about this, since it is utterly contrafactual.  I'm
sure GR would have been developed (though not in 1906!).  Einstein was
not the only person working on trying to come up with relavistic
theories of gravity.  Other people came up with some that were getting
sort of close (sorry, I don't have references on this - it would be fun
to know just *how* close).  And more importantly, the mathematical
infrastructure had already been laid by Riemann and was being studied by
Cartan and Hilbert, who were sort of into physics.  So I am quite sure
someone would have come up with GR after a while.
Newsgroups: sci.physics
From: parson_r@cubldr.colorado.edu (Robert Parson)
Subject: Re: Solid-state doesn't use QED! (Was Re: Particle Research)
Organization: University of Colorado, Boulder
Date: Sat, 7 Nov 1992 19:13:05 GMT

In article <BxA2GC.6yE@wsrcc.com>, alison@wsrcc.com (Alison Chaiken) writes:
> 
> You're wrong.  As far as the theory of the electron goes, QED has had
> no impact on solid-state physics whatsoever. 

 One counterexample (not "solid state", but certainly condensed matter):
 at large distances the interaction potential between neutral molecules is
 proportional to r**(-7) (Casimir-Polder potential) rather than r**(-6)
 (the usual London dispersion potential). This is a radiative correction;
 it can be understood physically by invoking retardation but a quantitative
 calculation requires QED (nonrelativistic QED suffices). Casimir's work
 on this was inspired by anomalous results concerning the stability of
 certain colloids. I do not know whether the Casimir-Polder force
 does in fact explain those colloid experiments (according to a ~1960
 review by Hirschfelder they do.) 
 What about polaritons? Much of their behavior can be understood physically
 in terms of purely classical electrodynamics, but a complete quantum-mechanical
calculation would have to treat the radiation field quantum-mechanically (long
ago I read a paper by Hopfield that does just that. This is way outside my
 field, though.)

> 
> Having said all that, the theories of broken symmetry and elementary
> excitations (Goldstone bosons) in solid-state physics have been heavily
> influenced by particle theories.  Here solid-state is using the
> _concepts_ of field theory, not the results!  My understanding is that
> particle theories have been in turn influenced by solid-state theories
> (e.g., non-perturbative field theories are greatly influenced by the
> BCS theory of superconductivity).
> -- 
 Which is why some condensed-matter physics books talk about the "Anderson-
Higgs mechanism."

Robert
From: rhatcher@fnala.fnal.gov
Newsgroups: sci.physics
Subject: Re: Scientists Plan to Blow Up the World!
Date: 6 Nov 92 08:59:12 -0600
Organization: Fermi National Accelerator Lab
NNTP-Posting-Host: fnala.fnal.gov

In article <MATT.92Nov5105233@physics2.berkeley.edu>, matt@physics2.berkeley.edu (Matt Austern) writes:
|> In article <mcirvin.720987478@husc8> mcirvin@husc8.harvard.edu
|> (Mcirvin) writes about the possibility that we are only living in a
|> false vacuum now and that high-energy experiments might catalyze a 
|> phase transition to the true vacuum:
|> 
|>|> I once opined to Eric Carlson that this was an idea that had been
|>|> insufficiently exploited in science fiction.  He pointed out to
|>|> me that "it would be a very short novel."
|> 
|> And I once suggested to Lawrence Hall that it was a truly wonderful
|> opportunity for rabble-rousing politics---definitely an argument
|> against the SSC that hasn't yet been sufficiently exploited by the
|> project's opponents.
|> 
|> I can just visualize the scene in Waxahachie: thousands of protestors
|> chaining themselves to the gates and throwing themselves in front of
|> bulldozers, holding up signs that say "Save the universe"!
|> --
|> Matthew Austern                   Just keep yelling until you attract a

Ah, if I remember right from the Michigan push to get the SSC, there *were*
detractors that did bring up such arguments.  Not quite as dramaticly as
organized protests, but more a wispering campaign.  There were also a
non-negligible number who got very much in arms over the part of the plans
leading to the beam dump that was labelled "abort".  Hit a "hot button" with
that one; I'm not sure they ever quite understood. :-(

-robert

 Robert W. Hatcher        | 256D Physics-Astronomy    | hatcher@msupa   (Bitnet)
 Software Tzar, Hunchback | Michigan State University | msuhep::hatcher (HEPnet)
 (517) 353-3008,-5180     | East Lansing, MI 48824    | hatcher@msupa.pa.msu.edu
From: john@jlc.mv.com (John Leslie)
Newsgroups: sci.physics
Subject: Re: EDUCATION, MONEY, AND THE FACTS OF LIFE
Date: 9 Nov 92 19:25:12 GMT
Organization: John Leslie Consulting, Milford NH

In article <Bx576y.Myp@mentor.cc.purdue.edu> (Herman Rubin) writes:
>
> You misunderstand what can and cannot be done by computers, or even by
> textbooks without some access to teachers.

   No, Herman, _you_ misunderstand.  But in any case, why are we talking
about "without access"?  This is the Net, remember!

> At the university level, those who have already taught the course can 
> produce a reasonable textbook using two to three man-years of hard work.

   And how often have we seen the estimates of man-years per day that go
into reading NetNews?  2-3 man-years isn't that much.

> When it comes to presenting ideas, I see no evidence at this time that
> computers can do a better job than written material.

   So what?  I can present _lots_ of evidence that they hold the child's
attention better.  Let us suppose that we present the information even
half as well as a textbook -- and then think about presenting manageable
chunks while that material is being discussed on the Net...

   sci.physics is a marvelous resource (if you have a good kill file :^)
where serious answers to elementary questions happen all the time.  I'm
sure there's some way we could tap into that.

John Leslie <john@jlc.mv.com>
Newsgroups: sci.physics
From: ddixon@nyx.cs.du.edu (David Dixon)
Subject: Classical eqns of motion->Quantum Mechanical
Organization: Nyx, Public Access Unix @ U. of Denver Math/CS dept.
Date: Mon, 9 Nov 92 17:17:14 GMT

Suppose I have some classical equations of motion of the form dL/dt = F(L),
where L is the angular momentum vector and F is a vector field.  Further
suppose that F contains a nasty dissipative term.  Is there a direct way
to get the corresponding quantum mechanical equations of motion?  Do I
try to go Lagrangian->Hamiltonian->dL/dt = i h_bar [L, H] (i/h_bar? h_bar/i?)
I vaguely remember that having a dissipative Hamiltonian does bad things
in quantum mechanics.

Actually, if somebody could just point me towards a book that would answer
these questions, it would be appreciated muchly.

					Dave
Newsgroups: sci.physics
From: m14494@mwvm.mitre.org (Mike White)
Subject: Re: Compelling Mysteries (II)
Organization: The MITRE Corporation
Distribution: na
Date: Tue, 10 Nov 1992 16:49:14 GMT

Cameron Randale Bass writes:
> I wonder if some of those people
> will oblige me by posting what they believe to be compelling
> mysteries or pressing problems in their particular field.

You don't have to look very far for compelling mysteries...
How about the two-slit electron diffraction experiment?
Yes, yes, I know the math, but it's just so... weird!
Fyneman (I think) said of it: "It is the only mystery".  And
how about Alley and Wickes' delayed-choice photon
switching experiments?  I mean, just what is reality,
anyway?  A quote from my undergrad physics prof said it best: 
"Nobody every really understands quantum physics,
they just get used to it".

************************
* These are my opinions only.*
************************
Newsgroups: sci.physics