HDTenEightyP/NetNews huggingface dataset:
From: matt@physics2.berkeley.edu (Matt Austern)
Newsgroups: sci.physics,news.groups,sci.misc
Subject: sci.physics.research: proposed moderation guidelines
Date: 7 Jan 93 19:00:00 GMT
Reply-To: matt@physics.berkeley.edu
Organization: Lawrence Berkeley Laboratory (Theoretical Physics Group)
NNTP-Posting-Host: physics2.berkeley.edu

Sci.physics.research is to be a newsgroup for discussions related to
current physics research.

This newsgroup is to be "lightly" moderated---that is, the moderators
will only reject clearly inappropriate postings, and will accept any
that has serious physics content or that is likely to be of interest
to an audience of professional physicists.  Clearly inappropriate 
postings include:
	(1) Personal attacks;
	(2) Discussion that isn't about or related to physics; 
	(3) Multiple responses that all say the same things; and
	(4) Crackpot postings that are "not even wrong."

An article that is rejected will be sent back to the author, perhaps
with the suggestion of a more appropriate newsgroup, or a suggestion
of how to revise it to make it acceptable.

Note that, in certain cases, articles about politics or philosophy are
appropriate to this group; for example, WHAT'S NEW is appropriate.
Such subjects, however, can easily drift into more general political
or philosophical discussions that have nothing to do with physics,
and, when this happens, the moderators will redirect the discussion to
a more appropriate group.

Note also that this newsgroup is not a peer reviewed journal; the
moderators are not referees or editors, and they do not have the time
to check whether the physics (or the grammar!) in each posting is
actually correct.  As long as an article is readable, and isn't
blatantly nonsensical, it's fine.

Finally, brief requests for facts are fine, so long as they aren't
already answered in the "frequently asked questions" (FAQ) list.
Replies to requests for information will be accepted if they (1) may
be of general interest, (2) don't become repetitive, and (3) don't
impose unacceptably heavy message traffic on the group.  Otherwise,
replies will be redirected to e-mail.  
--
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!
Newsgroups: sci.physics,news.groups,sci.misc
From: matmcinn@nuscc.nus.sg (brett mcinnes)
Subject: Re: sci.physics.research: proposed panel of moderators
Organization: National University of Singapore
X-Newsreader: Tin 1.1 PL4
Date: Fri, 8 Jan 1993 05:51:03 GMT

Incidentally, I hope that it is possible to ensure that the new group goes
out to all sites receiving sci.physics. For example, I cannot get
sci.math.research here.
Newsgroups: sci.physics
From: dseeman@novell.com (Daniel Seeman)
Subject: Re: Okay, it's not the inverse sprinkler problem...
Organization: Novell Inc., San Jose, Califonia
Distribution: sci
Date: Tue, 12 Jan 1993 21:21:40 GMT

In article <1993Jan12.160756.14894@linus.mitre.org> m14494@mwvm.mitre.org (Mike White) writes:
>Mark Schnitzius writes:
>> At first it seems that "hitting the clutch" would be the
>> proper answer, so your car would provide the least resistance
>> to the oncoming car.  But consider -- shouldn't your goal
>> be to reduce the sudden acceleration that you will be 
>> experiencing?  If that's the case, then maybe hitting the
>> brake would be the correct answer.
>
>It might be, if your car was incompressable.  In fact, most of
>your injuries would probably stem from deformation of the car, and
>subquent crush injuries and rupture of the gas tank and fire/explosion.
>You did't give enough information to answer the question: is the car in
>question a Volvo or a Pinto?
>
Good point.  You might add the Chevy truck to the Pinto reference.  Their gas
tanks can explode after impact too although you might find more fire and the
like if the Chevy gets hit from the side (T-boned, so to speak)...

dks.
Newsgroups: sci.physics
From: ghw@brahms.udel.edu (George Watson)
Subject: Re: "What's New" jan-08-1993
Summary: Anonymous ftp for archived "What's New"? 
Organization: University of Delaware
Date: Tue, 12 Jan 1993 17:56:23 GMT

Is there an anonymous ftp source of archived "What's New"?
Thanks.
(I am already aware of the pinet.aip.org availability and would like
to find a "free" source.)

-- 
George Watson                  | 
Dept. of Physics & Astronomy   |   Gosh darn the torpedos,
University of Delaware         |     full speed ahead!
ghw@brahms.udel.edu            |
From: jbaez@riesz.mit.edu (John C. Baez)
Newsgroups: sci.physics
Subject: Re: Why are elementary particles small?
Date: 6 Jan 93 23:26:33 GMT
Organization: MIT Department of Mathematics, Cambridge, MA

In article <1993Jan3.235010.17976@math.ucla.edu> barry@arnold.math.ucla.edu (Barry Merriman) writes:
>Why are elementary particles small?

Elementary particles are pointlike and points are small more or less by
definition.  

The above snide but true answer doesn't count bound states like protons
as being elementary.  One could ponder the properties of bound states
that were as big as a baseball... for example, a baseball is itself a
bound state!  Of course, a baseball consists of lots more elementary
particles than a proton does.  A bound state consisting of only a few
elementary particles but big as a baseball would probably be very weakly
bound hence too fragile to have much fun with.
From: sshankar@td2cad.intel.com (Sadasivan Shankar)
Newsgroups: sci.physics
Subject: Re: Different kinds of fluids (was: bird in plane)
Date: 11 Jan 93 22:05:41 GMT
Reply-To: sshankar@td2cad.intel.com (Sadasivan Shankar)
Organization: Intel Corporation, Santa Clara, CA USA


The relation between shear stress and rate of deformation in a Newtonian fluid can be
characterized as symmetric, isotropic, and linear.  Thus the shear stress is same in
all the directions in a Newtonian fluid unlike polymeric fluids.  

S.Shankar
Tech CAD
INTEL
From: dseeman@novell.com (Daniel Seeman)
Newsgroups: sci.physics
Subject: Re: infinite universe
Date: 5 Jan 93 16:29:52 GMT
Organization: Novell Inc., San Jose, Califonia

In article <1993Jan5.041650.7437@nuscc.nus.sg> matmcinn@nuscc.nus.sg (MAWENZI lieutenant of Kibo) writes:
>dseeman@novell.com (Daniel Seeman) writes:
>: On this very non-rigourous (even symplistic) level, there can be no boundary to
>                                   ^^^^^^^^^^^                            
>  This is my favourite neologism for 1993 so far.                         

Pardon my ignorance.  What new phrase has been coined here?  I don't understand
what you mean ;-)

dks.

ps. If you're flamin' me, go ahead and explain it.  I can take it ;-)
From: mcirvin@husc8.harvard.edu (Matt McIrvin)
Newsgroups: sci.physics
Subject: Re: infinite universe
Date: 9 Jan 93 17:58:50 GMT

Terry_Martin@mindlink.bc.ca (Terry Martin) writes:

>Questions by a non-scientist;

>a) Can matter and space occupy the same volume simultaneously?

I'd say so, by any reasonable definition-- without space you don't
have any volume in the first place.  

>b) We define the universe in terms of General Relativity and Quantuum
>Mechanics. I understand that these generalized terms describe the observable
>universe on cosmological and sub-atomic levels reasonably well, but are
>incompatible when combined in that they result in a singularity.

Singularities, in the general-relativistic sense, don't have anything to
do with quantum mechanics-- they happen in situations involving *classical*
matter in GR spacetime.  In fact, it's possible that quantum mechanics
may yet rid GR of singularities.  The problem that occurs when you try
to quantize GR by the usual methods is another kind of divergence; 
infinities occur that cannot be removed in the usual fashion.  

>If this is true, and we can have a universe which includes space-time but not
>matter, which by definition would also exclude gravity and quantuum
>mechanical effects, in what terms would the universe be described? (I assume
>it would contain energy)

A universe with no matter in which spacetime behaves non-quantum mechanically
may be completely described by a metric, a description of the geometry.
What the universe would actually be like would depend on, among other
things, whether there is a cosmological constant.  
-- 
Matt McIrvin         I read Usenet just for the	tab damage!
==== =======         = ==== ====== ==== === === === ======= 
Newsgroups: sci.physics
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Re: How moderation would work
Organization: MIT Department of Mathematics, Cambridge, MA
Date: Wed, 13 Jan 93 01:54:37 GMT

In article <m720wB1w165w@1776.COM> bob@1776.COM (Robert Coe) writes:
>There's been a lot said recently to the effect that the panel of moderators
>would (or should) vote on whether to accept a particular article.  Surely 
>that would be too cumbersome and slow! 

Indeed, I would never consent to moderate if I had to look at all
articles.  For one, I have other things to do.  For two, I go on
vacations now and then.  I expect to discuss only the most problematic
cases with other moderators, at least once things get going.
From: boswell@well.sf.ca.us (Gerard Van der Leun)
Newsgroups: sci.physics
Subject: Re: sci.physics.moderated - lectures?
Date: 12 Jan 93 22:24:38 GMT
Followup-To: sci.physics
Organization: edge

In article <C0r9pI.79v@well.sf.ca.us>, sarfatti@well.sf.ca.us (Jack
Sarfatti) wrote:
> 
> 
> I am getting good e-mail response to both my lecture threads on Feynman's
> QED papers and Kaiser's book of wavelets. 

I certainly hope so since readers of this group don't seem to want to do
any public follow-ups to the series.

> I suspect there should be a moderated sub-conference sci.physics.lectures
> separate from sci.physics.research.

I suspect that, even couched as "lectures", you would have trouble getting
them by reasonably sane moderators. Seeing as they are in numerous groups
already, putting them in one more would be a waste of bandwidth even if
we had a bit-pipe as big as the mind of God.
Newsgroups: sci.physics
From: marty@amaterasu.physics.uiuc.edu (Marty Gelfand)
Subject: Re: Wavelets & Coherent States ?
Organization: Department of Physics, University of Illinois at Urbana-Champaign
Distribution: usa
Date: Thu, 7 Jan 1993 03:27:04 GMT

In article <1993Jan6.230830.6733@galois.mit.edu> jbaez@riesz.mit.edu (John C. Baez) writes:
>In article <1993Jan3.211626.3723@EE.Stanford.EDU> siegman@EE.Stanford.EDU (Anthony E. Siegman) writes:
>>In article <qg62r5g@rpi.edu> sassoj@aix.rpi.edu (John J. Sasso Jr.) writes:
>>
>>>quantum mechanics.  Although I have has a basic course in Q.M., can anyone
>>>explain to me what coherent states are?  Do they have anything to do with 
>>>phase-space localization?
>>
>>   I can't explain them to you in a short note, but they are a
>>basically simple and also very effective way of rephrasing the quantum
>>theory of simple harmonic oscillators.  To find out about them do some
>>literature searching under the names of Glauber (Roy Glauber of
>>Harvard University) and possibly Louisell, and perhaps look for some
>>more modern and recent QM theory texts, not necessarily advanced ones
>>-- possibly by Cohen-Tannoudji, or Messiah.
    Another decent reference is the first chapter of Negele and Orland,
  Quantum Many-Particle Systems
>>
>>   I also think you are perceptive in noting a possible connection
>>between wavelets and coherent states.  Coherent states provide an
>>"over-complete" basis for the SHO, which means that the expansion of a
>>given arbitrary SHO state in coherent states is not unique (although
>>there are preferred ways to do the expansion), and I suspect the same
>>may be true of wavelets.
>
>Wavelets are a type of orthonormal basis of functions on the real line.
    That's just one kind of wavelet.  There's another flavor known as
  "continuous wavelets" which, like coherent states, form a massively
  overcomplete basis (for square-integrable functions) in which
  the coefficients in the expansion of the function in the basis
  are just the inner product of the function with the basis states.
  (For an overcomplete basis this is not true in general.)
  I'm told the standard reference on this topic is chapter 2 in Daubechies' 
  Ten Lectures on Wavelets; I haven't looked at it myself.
> [and more nice stuff from JCB on  wavelets and coherent states]
  Marty Gelfand  marty@amaterasu.physics.uiuc.edu
Newsgroups: sci.physics,news.groups
From: rvc40592@uxa.cso.uiuc.edu (Bob Cadman)
Subject: Re: sci.physics.research: proposed panel of moderators
Summary: I vote yes.
Organization: University of Illinois at Urbana
Date: Sat, 9 Jan 1993 03:18:31 GMT

sidles@stein.u.washington.edu (John Sidles) writes:
>If there hasn't been much discussion, what does that say about the need
>for sci.physics.research?

Maybe it says that everyone agrees it's a good idea and we should have
the vote as soon as possible.

>Except for the prospective moderators
>themselves, who else is calling for new group?

All right, then, despite the fact that it is costing hundreds if not
thousands of dollars to send this message everywhere, I'll say that I'd
like to see s.p.r. created, if the details can be ironed out, and I will
add that I don't read s.p. because the signal to noise ratio is too low.
(If another post in this thread is any indication of what has been going
on there, I haven't been missing much.)

>I hope these guys are not all scientologists!  There would be no
>way to replace them.  Sounds like a prescription for a self-perpetuating
>aristocracy to me.  Good thing the Constitution isn't set up this way.

It seems to me that in its own special way, Usenet is a
self-perpetuating aristocracy.  Deal with it.
-- 
Bob Cadman     (cadman@uiuc.edu)
A word is worth a thousand pictures.
Xref: sparky sci.physics:22151 rec.arts.startrek.tech:7232
From: johan@blade.stack.urc.tue.nl (Johan Wevers)
Newsgroups: sci.physics,rec.arts.startrek.tech
Subject: Re: Accellerating Spaceship (yet another bird in a plane)
Date: 6 Jan 93 12:21:04 GMT
Followup-To: sci.physics
Organization: Department of Physics, Eindhoven University of Technology.

jdsiegel@garnet.berkeley.edu (Joel Siegel) writes:

>>For example, if you had two chunks of matter, one negative and
>>one positive, the negative chunk would move away from the positive
>>chunk because of repulsion.  However, the positive chunk would move
>>toward the negative chunk, trying to catch up.  So, toss a chunk of
>>negative matter out the door of your spaceship, and away you go!

>Ahhh... perpetual motion?  That could be better than warp drive! :-)

Yes, if it was true. But matter with a negative mass would react just
the same as matter with a negative electrical charge. 2 negative
{charged or mass} particles attract each other, 1 negative and one positive
{charged or mass} particle repulse each other. And negative electricity
doesn't give you a perpetual motion :-(
-- 
********************************************************** 
* J.C.A. Wevers                *   The only nature of    * 
* johan@blade.stack.urc.tue.nl *   reality is physics.   * 
********************************************************** 
Newsgroups: sci.physics,sci.materials
From: kimmel@cortex.sai.vtt.fi     (Jyrki Kimmel)
Subject: Re: experimentalist issues
Organization: Technical Research Centre of Finland (VTT/SAI)
Date: Fri, 8 Jan 1993 06:21:21 GMT

In article <1993Jan7.162827.13371@news.cs.brandeis.edu> mcdougal@jensen.cc.brandeis.edu (Brendan A McDougall) writes:

>I think there is a need for a more timely forum.  Is there interest in  
>starting a sub-group, e.g. sci.hardsci.exp, that would encompass the needs  
>of all hard science experimentalists--engineers, chemists, mat sci, et  
>al.?  Or should one just post to these groups as they are?

I can relate to your problems, as the solutions seem similar to
ours (grab the phone). 

I suppose, however, that sci.research ought to be chartered to
cover experimental work. Or is it that you NEED a newsgroup
to be encouraged to submit articles on experiment related
items? If so, sci.experiment could be a good name for the
newsgroup. (WRT e.g. sci.comp-aided)

Jyrki


-- 
Jyrki Kimmel, VTT Medical Engineering Laboratory kimmel@cortex.sai.vtt.fi
signature in proposal in peer review phase (PPRP). Proposed motto:
"El{m{ on kivaa!" ("Life is fun!")  -Kaisa-Maria, age 3
From: paul@mtnmath.UUCP (Paul Budnik)
Newsgroups: sci.physics
Subject: Re: A proof that quantum mechanics is an incomplete theory
Date: 8 Jan 93 17:04:30 GMT
Organization: Mountain Math Software, P. O. Box 2124, Saratoga. CA 95070

In article <1993Jan7.175100.4450@lmpsbbs.comm.mot.com>, bhv@areaplg2.corp.mot.com (Bronis Vidugiris) writes:

> [...]
> My point, such as it was, was that I would expect simple-minded classical
> predictions to also hold true for QM, because in the limit for large number
> of particles QM results in classical predictions.  Especially for something
> simple-minded like a delay.  I just don't think that we are going to see
> anything other than the simple t = d/c sort of delay come out of any
> experiment.  The major place Maxwell's equations come into this simple
> formula is in any  necessary adjustment of 'c' from the free-space value,
> BTW.

There are two distances in this experiment. The probability of a joint
detection is equally influenced by *both* polarizer angles. By your argument
this would imply that the delay would be related to the larger distance.
I suspect you are right about this and quantum mechanics is wrong in its
prediction that the delay is indenedent of the larger distance.

> In spite of the fact that QM requires one to do odd things like sum intergals
> over all possible paths (at least using the Feynman approach) the results
> ultimately match the classical ones as far as delays go, (at least if the
> paths are of macroscopic length) - even though the method of arriving at the
> result is a lot different.

Not in cases where you have to use the assumption that the wave function
changes instantaneously when an observation is made. There is nothing
remotely resembling this in classical theory.

> As far as classical equivalents to the Aspect experiment go, I'm not as
> sure as you are that something roughly analogous couldn't be thought up with
> a pair of polarized beams randomly (but identically) phase modulated, but I
> haven't really thought this through.

I can be completely certain that you cannot reproduce the predictions of
quantum mechanics using any current physical theory if you do not also use
the assumption that the wave function changes instantaneously when an
observation is made. There is no other nonlocal law in all of contemporary
physics and thus there is no other way to get a prediction that Bell's
inequality is violated. This assumption will not be found in any classical
theory. In the near future I suspect it will not be found in any accepted
physical theory. I think my proof will be a first step in getting the
`ghosts and goblins' of action at a distance out of contemporary physics.

Paul Budnik
Newsgroups: sci.physics
From: jarleb@athena.uio.no (Jarle Brinchmann)
Subject: Re: Request info on Cold Dark Matter
Keywords: cold dark matter, cosmology
Reply-To: jarleb@athena.uio.no (Jarle Brinchmann)
Organization: Institute for Theoretical Astrophysics
Date: Fri, 8 Jan 1993 15:10:56 GMT


Chris Metzler writes:

> 2.  Hi Mike.  Hope things have gone well since Varenna.  I would take a
> small amount of exception with your statement that "COBE results have
> shown that minimal CDM is not correct, since it creates too much structure
> at small scales if one normalizes the distribution to the large (COBE)
> scales."  I would take exception to this.  Remember that the simulations
> people have done which have told them that there's too much structure on
> small scales assume that the collisionless particles in the N-body
> simulations are accurate tracers of galaxies.  I am NOT talking about
> spatial bias (biased CDM) here.  Galaxy formation simulations which include
> both N-body and hydro suggest that there exists velocity bias even in
> unbiased CDM models, whether from dynamical friction or from the
> nature of the environment galaxies are born into.  Thus, the whole
> "pairwise-velocity-dispersions are too high" problem may not even exist.
> You may be right, but I think the jury is still out; the impression
> I'm starting to get from the CDM gurus is 'hey, maybe unbiased CDM
> wasn't so bad after all.'
  
Maybe this is because they are _CDM_ gurus :-) ? I recently read (or is
reading) a preprint from A. Kashlinsky, in which he argues that with our
current observations of high-z objects, there is not easy to get enough
power on small scales with CDM. Not easy means virtually impossible in
his opinion, but then he is not very supportive of CDM.....

I think very many wants CDM to survive because it is quite well understood
and it has survived comparatively long. But if we shall start to use models
with mixed CDM and HDM or a non-zero cosmological constant, I see no 
aestethic reason for not having a tilted spectrum. IMHO both a mixed DM 
universe and a tilted spectrum contains some a priori unknown constants, 
and therefore I guess we can't say much. Too bad COBE gave us such results
it would have been much more fun if we could make everything as simple as
possible :-)


					Jarle.


--
      ---------------------------------------
       Internet: jarleb@medusa.uio.no         
       or        Jarle.Brinchmann@astro.uio.no
      ---------------------------------------

Newsgroups: sci.physics,alt.sci.physics.new-theories