HDTenEightyP/NetNews huggingface dataset:
From: dseeman@novell.com (Daniel Seeman)
Newsgroups: sci.physics
Subject: Re: in favor of a moderated physics group
Date: 11 Jan 93 19:28:02 GMT
Organization: Novell Inc., San Jose, Califonia

In article <5620032@hplsla.hp.com> dougp@hplsla.hp.com (Doug Passey) writes:
>I am no longer actively involved in physics, although my degrees are in the
>field.  I am now a software engineer, but like to keep up with developments in
>physics as best I can.  
>
>This notes group is a joke!  There are more postings here each day then on
>the rec.arts.startrek groups ... come on , we're talking physics here ... there
>can't be that much new, interesting stuff each day!  I don't like to have
>to sort out the crackpot stuff from the interesting news.  I would welcome 
>a moderated conference to filter out the junk ... but I would hope
>that interesting news is not filtered out as being to low level for a
>"research" news group.  I hope the moderators will keep in mind those of us
>who only browse this group and are not working physicists and not overly
>restrict the postings ... just filter out the crackpots.

I have been trying to stay away from this because i think the whole moderation
discussion is a bunch of hogwash.  But to this message i must reply.

What is "junk?"  Who are the "crackpots?"  I can understand completely that you
do not like to read some posts on the net, but maybe I do.  I do not think it
unreasonable to ask you to press the 'n' key a few dozen (hundred, thousand,
etc...) times, or to set up your kill file appropriately.  "Junk" as you (or
maybe as i) would describe it is not so to others, and there arguably are NO
"crackpots" in the world (please allow me to play devil's ---read Abian's---
advocate for just a moment).

You are your own best moderator.  If you don't like what your are reading, 
either sound off and try to point out what is wrong, or just don't read it.  But
do not try to get it banned from the net as you may be curtailing the interest
of another.

I just had to chime in on this one because of the reference about not overly
restricting working physicists but rather filtering the crackpots.  Watch out,
it has been said many times that working physicists ARE crackpots...

dks.

ps.  If you don't like what is on your T.V. set, TURN IT OFF!!!  If that ON/OFF
button is too hard to use, PULL THE PLUG. That'll do it for sure!
Xref: sparky sci.physics:22403 news.groups:25262 sci.misc:1989
From: bhoughto@sedona.intel.com (Blair P. Houghton)
Newsgroups: sci.physics,news.groups,sci.misc
Subject: Re: sci.physics.research: proposed panel of moderators
Date: 9 Jan 1993 21:05:14 GMT
Organization: Intel Corp., Chandler, Arizona
NNTP-Posting-Host: stealth.intel.com

In article <1993Jan8.030744.17741@infodev.cam.ac.uk> gjm11@cus.cam.ac.uk (G.J. McCaughan) writes:
>No, they are not all Scientologists. I have reason to believe that none
>of them is a Scientologist. If you're suggesting that they all represent
>some particular sort of ideology to which you object, it would be interesting
>to know what common ideology you have in mind...

I'd say they were all Gay Nazi Bikers for Christ,
but that's been taken already.

				--Blair
				  "Something about that
				   Newsgroups: line that
				   minds one of da Silvas..."
Newsgroups: sci.physics
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Re: Wavelets & Coherent States ?
Organization: MIT Department of Mathematics, Cambridge, MA
Distribution: usa
Date: Wed, 6 Jan 93 23:08:30 GMT

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.
>
>   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.
(Let's keep life simple and not talk about R^n.)  They have the
advantage of being "compactly supported" - each one vanishes outside of
some bounded interval.  This makes wavelets handier than Fourier
analysis in many contexts.  In Fourier analysis, one decomposes a
function into sines and cosines, which have "perfect pitch" (i.e., are
delta functions in momentum space) but "last forever" (i.e., are not
compactly supported in position space.)  Wavelets are compactly supported
in position space hence (by a nice theorem) not compactly supported in
momentum space - but one can make 'em fairly well localized in momentum
space.  

Coherent states are rather different.  They don't form a basis; they are
"overcomplete".  Basically, they are just functions of the following
form: a Gaussian translated by a certain amount and then multiplied by a
complex exponential.  If we make the Gaussian tall and skinny, we have a
function that's fairly well localized in position space; if we make it
short and wide, it's fairly well localized in momentum space.  If one is
looking for a quantum state that approximates a given classical state,
one is probably looking for a coherent state... they are often used for
that in quantum optics.  

Try:

 Klauder, John R.
     Coherent states : applications in physics and mathematical physics
[papers
   / compiled and introduced by] John R. Klauder, Bo-Sture Skagerstam.  
   Singapore : World Scientific, c1985.
Newsgroups: sci.physics,news.groups,sci.misc
From: mrmuon@next06pg2.wam.umd.edu (Eli John Hawkins)
Subject: reported dark matter observation
Organization: Workstations at Maryland, University of Maryland, College Park
Date: Tue, 5 Jan 1993 23:57:06 GMT

I saw a brief item las night on an overnight news show. It was something  
about dark matter having been observed with X-ray astronomy and that it is  
supposed to be enough to close the universe.
I imagine that someone on the net knows more about this.
Has this been published (if so, where) or just announced?:
What's the deal?
--
Eli Hawkins : mrmuon@wam.umd.edu
Newsgroups: sci.physics
From: abian@iastate.edu (Alexander Abian)
Subject: TIME HAS INERTIA   GOEDEL's THEOREM  att:  Reiners and Stiehm
Organization: Iowa State University, Ames IA
Date: Thu, 7 Jan 1993 19:46:16 GMT



STRICTLY FOR THE ARDENT AND DEVOTED READRERS OF  TIME HAS INERTIA


Dear Messrs  Reiners and Stiehm,

   Thank you for inquiring about my exposition of Goedel's Proof.
   I will try to post it  before the end of this week.  Sorry for
   the delay - I am quite busy today.

Please communicate with me via:  sci.physics  TIME HAS INERTIA  since
otherwise I may not get your messages.
   Thank you again for your interest.       Alexander Abian
  
-- 
   The tendency of maintaining the status-quo, Reaction to provocation and
                The tendency of maintaining again a status-quo.  
    TIME HAS INERTIA  and some energy is lost to move Time forward  
  E = mcc  (Einstein)    must be replaced by    E = m(0) exp(-At) (Abian)
From: carlip@landau.ucdavis.edu (Steve Carlip)
Newsgroups: sci.physics,alt.sci.physics.new-theories,sci.skeptic,alt.paranormal,alt.alien.visitors,alt.conspiracy
Subject: Re: The New Physics of "The Force" of "Star Wars".
Date: 4 Jan 93 17:46:17 GMT
Followup-To: sci.physics
Organization: Physics, UC Davis

I'm probably going to regret this follow-up, but there's enough almost-physics
here that I can't resist...

In article <C0B988.A5D@well.sf.ca.us> sarfatti@well.sf.ca.us (Jack Sarfatti) writes:
>[...]
>1. Looking at Feynman's classic 1949 papers on quantum electrodynamics
>(QED) from the 1992 perspective of quantum gravity suggests that the
>"ultra-violet catastrophe" is easily avoided by using the Planck length
>(i.e. 10^-5 grams = 10^-33 cm etc.) as the high-momentum/short wavelength
>cut-off.

Easily?  Then you should by all means publish your results.  The speculation
that Planck length effects cut off divergences in quantum field theory has
been around for years, and a lot of interesting work has been done, but no 
one has yet managed to find a way to consistently implement such a cutoff.
Do you have a way to preserve approximate Lorentz invariance at low energies?
Do you know how to avoid the divergences of quantum gravity itself?  Is your
cutoff at exactly the Planck length (no extra factors of two or pi)?  Why?
What variables are you applying this cutoff to?  In general relativity,
you can't just Fourier transform between position and momentum space, so a
momentum cutoff is not necessarily equivalent to a length cutoff.  How do
you deal with overlapping loops in Feynman diagrams?  Etc... The idea that
quantum gravity cuts off divergences is a very nice one, and I hope it's
true, but we're going to have to know a hell of a lot more than we do now
before this becomes more than an interesting conjecture.

>QED is "semi-classical" in that the spacetime metric is classical only the
>photon and electron fields are quantized.  The metric quantum fluctuates so
>strongly at the cut-off that Lorentz symmetry breaks down. There is no
>smoothness, no differentiability there.  The geometry of quantum gravity is
>fractal! Note that in semiclassical QED the worldlines of photons and
>electrons are fractal but the metric is not.

If the metric is nontrivial, Lorentz invariance breaks down independent of 
how strong the fluctuations are.  And if by "the worldlines of photons and 
electron" you mean "the paths that contribute to the functional integral,"
then you're not quite right here --- in quantum mechanics, nowhere-smooth
paths dominate, but in quantum field theory, the dominant configurations
are not even continuous (nothing so neat as a "fractal").  As for quantum
gravity, no one knows what the geometry is like, or even whether geometry
makes sense at the Planck scale.  Again, if you have some real evidence for
"fractal geometry," please publish!

>[much more deleted]

Steve Carlip
carlip@dirac.ucdavis.edu
Newsgroups: sci.physics
From: matt@physics2.berkeley.edu (Matt Austern)
Newsgroups: sci.physics
Subject: Re: infinite universe
Date: 4 Jan 93 11:10:09
Organization: Lawrence Berkeley Laboratory (Theoretical Physics Group)
Reply-To: matt@physics.berkeley.edu
NNTP-Posting-Host: physics2.berkeley.edu
In-reply-to: dseeman@novell.com's message of 4 Jan 93 18:42:45 GMT

In article <1993Jan4.184245.28970@novell.com> dseeman@novell.com (Daniel Seeman) writes:

> On a philosophical level, what is the meaning of a Universe with a
> finite size?  What is happening at the boundary between that which
> is the Universe and that which is not?  And, what would happen if I
> stepped into that region which was defined as the "Non-Universe?"
> 
> On this very non-rigourous (even symplistic) level, there can be no
> boundary to the Universe. Any "region" found outside the Universe
> would automatically become part of our Universe (which would have
> just expanded to include the "region" you were interested in).  I
> belive this provides a qualitative descript ion of the "Infinite
> Universe."
> 

Saying the the universe does not have a boundary is not the same as
saying that it is infinite.

To use the classic analogy: the two-dimensional surface of a balloon
does not have a boundary.  However, this surface has finite volume.
--
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: jarleb@athena.uio.no (Jarle Brinchmann)
Subject: Re: Omega
Reply-To: jarleb@athena.uio.no (Jarle Brinchmann)
Organization: Institute for Theoretical Astrophysics
Date: Mon, 11 Jan 1993 15:11:52 GMT


In article <1993Jan10.225009.169@vms.huji.ac.il>, tabitha@vms.huji.ac.il writes:
|>From: tabitha@vms.huji.ac.il
|>Newsgroups: sci.physics
|>Subject: Omega
|>
|>A question from a non-physicist regarding the current thread
|>on omega.
|>
|>What is the generally accepted range of values for
|>the critical density of the universe?
|>
There are basically two important omega's in cosmologoy:

1. Omega_baryon which measures how much baryonic matter there is in 
   the universe. This is measured by estimated the amount of light
   elements, deuterium (which aboundance is quite a good measure of
   the omega_baryon. It's value today is in the range 0<omega_baryon<0.2
   (The lower bound is often quoted to be 0.01 or something), but one
   has to keep in mind that there are quite large uncertinties in the
   measurements. Often the lower bound is quted as being the "best"

2. Omega_0, which is the critical density today. It is widely accepted that
   it's value is between 0.01 and 1. One of the most important tests are
   the age test, which says that the universe must be older than it's 
   occupants. This sets a constraint on Omega_0, and even though one 
   has to adopt a universe model to estimate the universe' age, I guess
   few believs Omega_0 to be (much) more than 1. 

Another important aspect is that inflation, which is a theory that gives
the universe an inflationary epoch in the past, where it expanded exponentially,
gives an omega_0 that is _very_ close to 1. (See e.g. Narlikar and 
Padmanabhan's article in Annual Rev. Astron. Astrophys. 1991).  So that
is the value for theorists. I should add that this is not completly correct,
what is supposed to be =1 is the sum Omega_0+lambda_0, where lamda_0 is a
normalized cosmological constant, a good account of measurements of lamda
is given in Lahav et. al. Mon. Not. R. astr. Soc (1991) 251.  


					Jarle.




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

Newsgroups: sci.physics,sci.math
From: tim@iss.nus.sg (Tim Poston)
Subject: Re: Why no Nobel Prize in Math?
Organization: Institute of Systems Science, NUS, Singapore
X-Newsreader: Tin 1.1 PL4
Distribution: na
Date: Mon, 4 Jan 1993 09:41:08 GMT

jcf@world.std.com (Joseph C Fineman) writes:
: *Biologists*, on the other hand.... %^)

I don't know prostitution statistics;
but someone who worked at a conference center told me that

(a) Natural scientists could be trusted to put money in the box
    for teabags, beer, etc., left out: social scientists could not.

(b) For late-night movement from bedroom to bedroom,
    nobody could equal the marriage guidance counsellors.

Tim
From: paj@uk.co.gec-mrc (Paul Johnson)
Newsgroups: sci.physics
Subject: Re: sci.physics.research: proposed panel of moderators
Date: 11 Jan 93 11:28:10 GMT
Reply-To: paj@uk.co.gec-mrc (Paul Johnson)
Organization: GEC-Marconi Research Centre, Great Baddow, UK

In article <478@mtnmath.UUCP> paul@mtnmath.UUCP (Paul Budnik) writes:

>1. It is a bad idea to have the word crackpot in the charter. ...

I gather that journals such as Nature refer to these articles as "too
speculative".  If the charter calls for the rejection of "overly
speculative" articles then that would be polite but firm.

Paul.
-- 
Paul Johnson (paj@gec-mrc.co.uk).	    | Tel: +44 245 73331 ext 3245
--------------------------------------------+----------------------------------
These ideas and others like them can be had | GEC-Marconi Research is not
for $0.02 each from any reputable idealist. | responsible for my opinions
Newsgroups: sci.physics
From: sarfatti@well.sf.ca.us (Jack Sarfatti)
Subject: re: private e-mail
Organization: Whole Earth 'Lectronic Link
Date: Sat, 9 Jan 1993 01:45:55 GMT


Apparently I inadvertently posted private e-mail here. I thought it was
a copy of a public post that sent to me as a courtesy because the header
looked like it came from sci.physics. Sorry, it was not intentional.
Xref: sparky sci.physics:22405 news.groups:25265 sci.misc:1991
From: bhoughto@sedona.intel.com (Blair P. Houghton)
Newsgroups: sci.physics,news.groups,sci.misc
Subject: Re: sci.physics.research: proposed panel of moderators
Date: 9 Jan 1993 21:21:49 GMT
Organization: Intel Corp., Chandler, Arizona
NNTP-Posting-Host: stealth.intel.com

In article <1993Jan8.174635.20821@ulrik.uio.no> jarleb@medusa.uio.no (Jarle Brinchmann) writes:
>Just a thought, quite a few agree that there is too few research level
>postings, but how many researchers are aware of usenet news ?
>I think I'll see how sci.p.research will develop, and thereafter (if as
>I assume it is successful) try to get some of the researchers at my 
>institute to subscribe to the group...
>(Of course I'm somewhat naive since I hope these people would have time 
>to answer, but one can always hope)
>As to why I haven't tried this with sci.physcis, I guess the answer gives 
>itself : Too much noise, too much to catch up with if you've been away
>for a while. 

You mean these people you wish to cooperate are constitutionally
opposed to making an effort.

This is consistent with the facts, since if more competent
and reasonable individuals were to contribute to sci.physics,
the noise level would not be as large as the signal level,
and we would not perceive a problem (this is an editorial
"we;" I never perceive a problem when free speech is the
issue) to be solved by limiting their potential access.

I expect that merely clearing the dance floor will not
result in the jitterbugging of wallflowers.

				--Blair
				  "The President's Dilemma."
From: paul@mtnmath.UUCP (Paul Budnik)
Newsgroups: sci.physics
Subject: Re: Quantum Mechanics Incomplete
Date: 9 Jan 93 23:23:29 GMT
Organization: Mountain Math Software, P. O. Box 2124, Saratoga. CA 95070

In article <93009.130058MRG3@psuvm.psu.edu] , MRG3@psuvm.psu.edu writes:
] [...]
]  The EPR experiment has been analyzed in the context of the relative state/
]  many worlds interpretation by Don Page and in the context of the
]  consistent histories interpretation by Bob Griffiths.  (Sorry, I do not have
]  the exact references available).  Neither of these interpretations
]  contain a catostrophic "collapse of the wave function", but are consistent
]  with the "usual" results.
]  I am by no means certain, but the impression I get is that
]  Paul's arguments are interpretation dependent.  On the other hand,
]  I will NOT argue that QM is necessarily complete. ;)

I do not believe my analysis is interpretation dependent. Please see the
following article on `The instantaneous transfer of information in QM
calculations' for a full explanation. You do not need to use collapse
but you need some equivalent nonlocal process. You need to assume that
the wave function you use in calculations changes instantaneously or
you simply cannot get the standard quantum mechanical predictions.

Paul Budnik
From: rhine@bigbird.csd.scarolina.edu (Andrew P. Rhine)
Newsgroups: sci.physics
Subject: re: The Big Bang Never Happened
Date: 6 Jan 1993 17:44:25 -0500
Organization: Univ. of South Carolina, Columbia
NNTP-Posting-Host: bigbird.csd.scarolina.edu
Summary: comment on evidence/
Keywords: cosmology big bang COBE

In response to Bill Wadge's recent post on Lerner's book:
I haven't read the book and don't know about any specific arguments made
therein, but it would seem that opposition to the big bang would have been
dealt a major blow by this year's results from COBE and recent observations
(by the balloon-based instruments) supporting it.
 Incidentally, I heard a lecture by Michael Turner (the U. Chicago physicist)
at Lawrence Livermore Natl. Lab shortly after the COBE results were made
public, and Turner made several (good-natured and quite funny) pokes at
Lerner's hypothesis, using slides titled "The Big Bang REALLY Happened!" and
the like... :)

Andrew Rhine
student, University of South Carolina

Newsgroups: sci.physics,news.groups,sci.misc
From: mwj@beta.lanl.gov (William Johnson)
Subject: Re: sci.physics.research: proposed panel of moderators
Summary: Oops.  Forgot a smiley.  My apologies to Mr. Sidles. 
Organization: Los Alamos National Laboratory
Date: Fri, 8 Jan 1993 23:35:02 GMT

I wrote:
>John Sidles raises a number of questions, some of which have been dealt
>with by other people already, but I will hack away at them anyway ...
[much stuff deleted]
>>which have sharply deliminted subject areas.  Perhaps I'm wrong... 
>
>You are.

Oops.  That should have read

>You are. :-)

It was not my intention to insult Mr. Sidles or to rub his nose in anything.  I
*do* think he's wrong, but his points are cogently made.  My line was supposed
to be jocular but didn't come out that way owing to typing too fast and 
omitting the smiley.  I've offered Mr. Sidles my apology via e-mail.

-- 
Bill Johnson				| My suggestion for an Official
Los Alamos National Laboratory		| Usenet Motto: "If you have nothing
Los Alamos, New Mexico USA		| to say, then come on in, this is the
!cmcl2!lanl!mwj (mwj@lanl.gov)		| place for you, tell us all about it!"
From: bweiner@ruhets.rutgers.edu (Benjamin Weiner)
Newsgroups: sci.physics
Subject: Re: Ansatz (as used in mathematical physics)
Date: 11 Jan 93 23:17:10 GMT
Organization: Rutgers Univ., New Brunswick, N.J.

jac@ds8.scri.fsu.edu (Jim Carr) writes:
>1) The word is taken from a German word that is not spelled quite the 
>   same way in its dictionary entry.  I know because I tried to look 
>   it up once, could not find it,  ...

I'm actually a little surprised by this, because I found "ansatz"
in a *pocket* Deutsch-English dictionary, the kind that's only about
2 by 3 inches big - defined as "start."  And incidentally, apparently
"Haaransatz" means "hairline."
From: gt1057a@prism.gatech.EDU (gt1057a JOHNSTON,KEITH)
Newsgroups: sci.physics
Subject: Gravity & Rubber Sheet Analogy Problem
Summary: What pushes the ball down the sheet?
Keywords: gravity, general relativity
Date: 12 Jan 93 00:39:01 GMT
Distribution: usa
Organization: Georgia Institute of Technology

In almost all explanations of gravity as warped space, the analogy
used is two-dimensional.  A mass deforms a "rubber sheet", causing
a depression in the two dimensional space.  Then, when an object 
approaches the mass, it takes the shortest straight line on the
sheet, which looks like a curved path to the people living in the
two dimensional universe.

But what if the first mass is Earth, and I set the moon in its
depression, with no initial velocity.  What would pull it "down"
toward the Earth, whicsits at the b bottom?  Why wouldn't it
just sit there in the depression?  Unless there is some other force
pushing it down the slope, which would mean an external "gravitational"
force outside the rubber-sheet universe, why would it move?

						Keith J

-- 
JOHNSTON,KEITH BARKER
Georgia Institute of Technology, Atlanta Georgia, 30332
uucp:	  ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!gt1057a
Internet: gt1057a@prism.gatech.edu
Newsgroups: sci.physics,sci.materials