HDTenEightyP/NetNews huggingface dataset:
From: sichase@csa1.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: TIME HAS INERTIA
Date: 9 Nov 1992 13:39 PST
Organization: Lawrence Berkeley Laboratory - Berkeley, CA, USA
Distribution: world
NNTP-Posting-Host: 128.3.254.196
News-Software: VAX/VMS VNEWS 1.41    

In article <1992Nov09.192052.25358@bas-a.bcc.ac.uk>, ucap22w@ucl.ac.uk (Martin S T Watts) writes...

>balanced - why can't you? For another thing, they are not. The one thing that
>you give Einstein credit for is something he probably never said. As Hermann
>Bondi has pointed out [Physics Bulletin _38_ (1987) p62], in all known physical
>processes energy and mass are in fact conserved separately. Energy has mass
>is a more useful statement than energy and mass are equivalent.

Maybe so, in all physical processes known to Hermann Bondi!  But any 
student who has spent two days in a particle physics class knows better.
And how clever of you to reference a magazine so obscure that even *I*
couldn't find it, with all the resources of the University of California
Library system at my disposal.  I am told by our local LBL physics librarian
that Physics Bulletin was a cross between the APS bulletin with it's
abstracts, and a small-scale Physics Today, with newsy items, appointments,
obits, that sort of thing.  It has been replaced by Physics World.  The
U.C. Library, which saves office memos and old toilet paper, never bothered
to keep its copies of Physics Bulletin.

So I guess that the wisdom of Hermann Bondi is just lost to me...

-Scott
--------------------
Scott I. Chase			"It is not a simple life to be a single cell,
SICHASE@CSA2.LBL.GOV		 although I have no right to say so, having
				 been a single cell so long ago myself that I 
				 have no memory at all of that stage of my 
				 life." - Lewis Thomas
From: andrew@rentec.com (Andrew Mullhaupt)
Newsgroups: sci.physics
Subject: Re: Religion & Physics Don't Mix
Date: 6 Nov 92 15:49:32 GMT
Organization: Renaissance Technologies Corp., Setauket, NY.

In article <1d9lk2INN73@agate.berkeley.edu> emarkp@soda.berkeley.edu (E. Mark Ping) writes:
>In article <1d9fa5INNoc6@chnews.intel.com> bhoughto@sedona.intel.com (Blair P. Houghton) writes:
>}The existence of physics belies the existence of the gods.
>
>Wait a second.  Do you think you can elaborate on that conclusion?

Not only that, but can it get into Phys. Rev. Letters?

On this whole subject, I think we can improve the SNR with the following
policy:

Anyone serious about claiming that science implies that there is or is
not God should be asked to provide references in _Phys. Rev. Letters_ since
a physical fact of this magnitude is sure to be reported there. Failing
this, the aspiring physical (a-)theologian should be asked to publish
his result there first. Then there will be little argument what _is_ and
_isn't_ demanded of the scientist's beliefs.

The relation between God, or even the idea of God and physics is important.
But truth told, science does not answer this question, and the more respectable
religions have learned that God did not make this one so simple. A successful
religion is for more or less obvious reasons necessarily persistent over many
human generations and accessible to, and pertinent to the majority of humans.
The explication of the actual relation of God to physics is going to fail to
be part of a successful religion for these three reasons, even if through the
religion's action some believers can become aware of the truth.

Later,
Andrew Mullhaupt

P. S. In view of the mechanics involved Olympic sport _curling_ it might
be better for sci.physics to seriously consider Sportsmanship vs. Geology.

Newsgroups: sci.physics
From: zellner@stsci.edu
Subject: Re: Do Balloons fly?
Organization: Space Telescope Science Institute
Distribution: na
Date: Fri, 6 Nov 1992 00:04:22 GMT


My goodness!  If we cannot do sophomore physics, how can we settle questions
about manifolds and Higgs bosons?

  >>  Thus, consider this: If the air surrounding the balloon had exactly 
  >>  the same density on all sides, then the balloon would not move (I 
  >>  think).
  > 
  >   No, actually it would sink, I think, because there is still the effect
  >   of gravity.

Double nonsense.  A gas cannot have uniform pressure in a gravitational 
field, not in hydrostatic equilibrium.  If it did, the gas would move 
around until it developed pressure differentials such that each volume 
element would have a pressure gradient between top and bottom equal to its 
weight.  

In a perfect gas the density is proportional to pressure.  In a liquid like
water or oil the density is almost independent of pressure, but the above
requirements of hydrostatic equilibrium are preserved in either case.

Now for balloons.  We can think about an infinitely stretchy balloon, which
will always maintain the same pressure inside as the air outside, and fill it 
with helium or hydrogen, which are less dense than air at the same pressure.
Or we can imagine a perfectly rigid balloon, the volume of which doesn't 
change with outside pressure, either empty (vacuum) or containing any mass
(composition irrelevant).  Or you could take an intermediate case. 

In any case it's the outside pressure gradients that count.  If the net 
pressure gradient is greater than the weight of the balloon, it will rise.  
If the pressure gradients are less than the weight of the balloon, it will
sink.  Of course if there is no gravity and no pressure gradients, it will go
nowhere except for small random forces like Brownian motion. 

As someone pointed out, you can come to the same conclusions by thinking about
gravitational potential, which is really just force integrated over distance. 

  > If you had a very long and very skinny baloon, would it rise faster
  > floating vertically than horizontally, e.g. imagine a baloon the
  > shape of a meter stick. 

Now that's a more interesting question.  You can answer it the hard way, by
integrating pressure over the surface area, or you can just think about 
gravitational potential ...

Ben

Newsgroups: sci.physics
From: gsmith@lauren.iwr.uni-heidelberg.de (Gene W. Smith)
Subject: Re: GR with no Einstein? (Was: Re: No big crunch?)
Organization: IWR, University of Heidelberg, Germany
Date: Tue, 10 Nov 92 17:41:54 GMT

In article <1992Nov9.182446.13635@murdoch.acc.Virginia.EDU> crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:

>     Though many people were working on gravitation, and always had been
>     working on gravitation (and there are still people working on 
>     alternatives), it wasn't like there was any vastly compelling reason to 
>     overthrow Newton.

Once you've bought special relativity (and about that you have no
choice) you've *got* to work on alternatives to Newton.  Moreover, you
are forced into nonlinear alternatives.  I think by working up from
the linearization, you would be led to a local theory which was
Einstein's locally, and from there it would become obvious.

Basically, what I am saying is that Einstein's theory in its pure (no
cosmological constant) form is the simplest classical theory uniting
gravitation with special relativity, and so would have been discovered
eventually--in the 40's or 50's, say.


-- 
     Gene Ward Smith/Brahms Gang/IWR/Ruprecht-Karls University 
               gsmith@kalliope.iwr.uni-heidelberg.de
Newsgroups: sci.physics,sci.math
From: pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt)
Subject: Re: graphical humping terminology
Organization: Computer Science Department,  Stanford University.
Date: Thu, 12 Nov 1992 03:39:57 GMT

In article <1992Nov11.063332.22820@galois.mit.edu> jbaez@riesz.mit.edu (John C. Baez) writes:
>>In article <ETHANB.92Nov9155340@ptolemy.astro.washington.edu>
>>ethanb@ptolemy.astro.washington.edu (Ethan Bradford) writes:
>>>The simple explaination of why yellow monochromatic light looks the
>>>same as equal combinations of green and red light is that the color
>
>(Picturesque solutions deleted.)  I agree with your annoyance
>completely.  Gaussians are very useful but pretending that every
>molehill or mountain is a Gaussian can lead to lots of errors - so it's
>good that mathematicians have a technical term for the kind of function
>you are referring to.  It's called a "bump function", or "bump".

Vision physiologists call it a "peak function" or "peak".
-- 
Vaughan Pratt
From: columbus@strident.think.com (Michael Weiss)
Newsgroups: sci.physics
Subject: Re: GR with no Einstein? (Was: Re: No big crunch?)
Date: 9 Nov 92 10:42:45
Organization: Thinking Machines Corporation, Cambridge MA, USA
	<1992Nov6.042306.899@murdoch.acc.Virginia.EDU>
	<1992Nov6.232435.15628@galois.mit.edu>
	<1992Nov7.034056.1944@murdoch.acc.Virginia.EDU>
NNTP-Posting-Host: strident.think.com
In-reply-to: crb7q@kelvin.seas.Virginia.EDU's message of 7 Nov 92 03:40:56 GMT

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.

   In article <1992Nov6.232435.15628@galois.mit.edu> jbaez@riesz.mit.edu
   (John C. Baez) writes: 

   >Oh good, let's argue about this, since it is utterly contrafactual.  I'm
   >sure GR would have been developed (though not in 1906!)....

In fact, there was a fairly extensive thread on this topic about a year
ago.  Without trying to summarize, let me repeat 4 points people made:

  (1)   Pais' biography of Einstein provides much insight into the
    	convoluted intellectual history of the actual birth of GR,
    	primarily from Einstein's viewpoint of course, but also with an eye
    	towards other contemporary efforts (e.g., Nordstrom's theory).

  (2)	Other very different paths to GR exist.  MTW mentions a "graviton"
    	based approach, worked out apparently by Feynmann.  You don't get a
    	consistent unification of QM with GR, but you can somehow tweak out
    	Einstein's field equations.  This was cited as an argument that GR
    	was "inevitable", once quantum field theory was developed.

  (3)   One does have to decide what "GR would have been developed" means.
    	Would it count to have a theory equivalent to GR, not generally
    	accepted but merely one of a welter of competing theories?

  (4)   And finally, from Twain we can crib the granddaddy of
    	counter-factual assertions:  If Walter Scott hadn't written any
    	novels, there wouldn't have been a Civil War.  [OK, that's not
	exactly was Twain said.]
From: mcrae@husc8.harvard.edu (Andrew McRae,   ,,)
Newsgroups: sci.physics
Subject: Re: Do Balloons fly?
Date: 6 Nov 92 22:02:01 GMT
Article-I.D.: husc3.1992Nov6.170202.17174
Reply-To: mcrae@husc8.harvard.edu
Originator: mcrae@husc8.harvard.edu

In article <1992Nov6.152707.8015@newshost.lanl.gov>, u108502@beta.lanl.gov (Andrew Poutiatine) writes:
> Secondly, although Andrew McRae's example is thought provoking, it is only
> that, since if in a gravitational field you somehow removed the pressure
> gradient, there would be nothing to hold the air in place, and it would
> accelerate constantly, as would the balloon, in the direction of the gravity
> vector.
> You simply cannot hold air in its place without a pressure gradient in a grav-
> itational field.

That's why I wrote:

>>                                         So consider a helium balloon in a
>>closed room with constant (to a close-enough approximation) pressure
                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>throughout, so that the balloon's volume is independent of its position.

If you can show that the approximation fails, I'd be fascinated. I only
introduced it to avoid having to worry about the details of the balloon
expanding as it rose -- in fact, I'm sure that replacing it by the
assumption that "no matter where the balloon is in the room, it displaces
air that weighs more than it does" allows the argument to go through
unchanged.

Of course, one should _expect_ that the balloon's behaviour could be
explained both by considering the forces that act and by considering
conservation of energy -- it always works that way! (I just think that in
this case, the energy argument is a damn' sight simpler!)

Andrew.

-- 
Andrew McRae                       Internet: mcrae@husc.harvard.edu
                                     BITnet: mcrae@HUSC
Newsgroups: sci.physics
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Re: Compelling Mysteries (II)
Summary: Gamma ray bursters
Organization: MIT Department of Mathematics, Cambridge, LA
Date: Wed, 11 Nov 92 05:29:08 GMT

In article <1992Nov10.203037.13332@sfu.ca> palmer@sfu.ca (Leigh Palmer) writes:

>What are the gamma ray bursters? One of the arguments advanced by
proponents of orthodoxy on the first conundrum was that annihilation
radiation was not seen from intergalactic space. Could be we've started
to see some? Could be we've just started to look for it.

Hmm.  Weird that it only occurs for short bursts, then.

I listen to "Earth and Sky," a public radio show that airs in the middle
of "Morning Edition" here in Riverside.  Yesterday they said that
someone is trying to use gamma ray bursters to investigate dark matter.
I guess the idea is that if dark matter is fairly big hunks of stuff
(comet-sized??) it should cause some distinctive dispersion in the gamma
rays.  Does anyone know anything about this idea?  It's not clear to me
how much info one can get without understanding the bursters at all.


Newsgroups: sci.physics
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Re: Sarfatti errata
Organization: MIT Department of Mathematics, Cambridge, MA
Date: Fri, 13 Nov 92 21:18:22 GMT

In article <1dsscsINNlci@iskut.ucs.ubc.ca> ramsay@unixg.ubc.ca (Keith Ramsay) writes:
>I am open to suggestions about this discussion with Sarfatti, as to
>whether this is the best way to deal with him. What I want most is to
>avoid anyone being convinced by mistaken arguments here. Sarfatti
>regularly states conclusions based on his arguments as fact, and I
>don't want anyone misled. On the other hand, it may be that I am
>really addressing myself to an audience of just one, i.e., Sarfatti
>himself.

Your persistence has been admirable but clearly it will never equal
Sarfatti's.  So at some point you will have to say, "I give up, but what you
are writing is wrong" - and perhaps occaisionally offer your
transcripts of the argument to any newcomer netters who may be
interested in Sarfatti's work.  
Newsgroups: sci.physics
From: jhh@waldzell.physics.yale.edu (Jim Horne)
Subject: Re: New Group sci.physics.orthodox
Organization: Yale University, Department of Computer Science, New Haven, CT
Date: Mon, 9 Nov 1992 13:57:19 GMT

In article <1deevpINNl33@bigboote.WPI.EDU> phillies@bigwpi.WPI.EDU  
(George D. Phillies) writes:
> Is it just me, or is the crackpot and fringe material
> drowning out the real physics?  Perhaps it is time for
>  
> sci.physics.orthodox (moderated?)
> 

I think a much better name would be sci.physics.research, and it
would have to be moderated, though lightly. There is already a  
successful moderated group sci.math.research which could serve
as an example of how to encourage substantive discussions of current
research.

> My motivation for this is the suspicion that this group 
> is not in contact with the physics community at all.  
> 
> George Phillies
> phillies@wpi.wpi.edu

Yes, very few real physicists read sci.physics. Most have been driven
out by the crackpots.

---------------------------------------------------------------------
Jim Horne
jhh@waldzell.physics.yale.edu
 
Xref: sparky sci.physics:18711 sci.math:14788
From: ask@ucscb.UCSC.EDU (Andrew Stanford Klingler)
Newsgroups: sci.physics,sci.math
Subject: Re: Covariant vs. Lie Derivative in Gen. Rel.?
Date: 11 Nov 1992 22:20:47 GMT
Organization: University of California; Santa Cruz
NNTP-Posting-Host: ucscb.ucsc.edu


In article <1drukoINN801@darkstar.UCSC.EDU> ask@ucscb.UCSC.EDU (Andrew Stanford Klingler) writes:

>JB:
>To repeat: The connection allows you to compare tangent vectors at two >>points of the manifold given only a curve connecting them; the Lie
>derivative requires a whole vector field, to generate a flow that "drags
>tensors along". 

I had replied:
:The distinction you're making sounds kind of phony; after all one can
:define a connection using a vector field or a field of one-forms (I may
:be limiting myself to principal fiber bundles here).  It seems like the
:flow is just buried in the structure for a connection (in some sense a
:connection gets you "more than a flow" - the local family of geodesics
:through a point).  Without a connection, you have no way to compare vectors
:at two different points, so you have to transport tensors out, then back
:to the same point and compare them there.  With a connection, you have
:"flow in every direction" (geodesics thru the point) so parallel transport
:vectors from a point to any other point and compare them there.  From this
:point of view Lie derivatives and covariant derivatives represent the
:same geometric thing, I think.  Am I way wrong here?

Sorry, I just want to head off criticism at the pass here. Of course if you
define your connection using a vector field, that vector field lives in the
tangent space to the fiber bundle (in some cases T(TM)) rather than TM.  Of
course that's how you get the generalized "family of flows" - you have a
family of vectors corresponding to each point of TM, rather than just a
single vector field on TM.

Newsgroups: sci.physics
From: peten@iat.holonet.net (Pete Norton)
Subject: Re: Splitting physics conference&multiple listings.
Organization: HoloNet (BBS: 510-704-1058)
 
Date: Thu, 12 Nov 1992 23:44:58 GMT

sarfatti@well.sf.ca.us (Jack Sarfatti) writes:
: 
: I suggest that sci.physics be split into three sub-conferences:
: 1. sci.physics.orthodox
: 2. sci.physics.foundations (where FTL & philosophy etc. stuff would be)
: 3. sci.physics.education (questions of pedagogy, for students etc.)
: 
: I volunteer to edit 2.
: 
: I notice lots of multiple postings between sci. math and sci.physics - yet
: when I put some optics related stuff in sci.optics I was immediately jumped
: upon for wasting bit space with multiple listings - what gives? I was
: told that the objection had nothing to do with content or value of the
: posting.
: PS the review of Gleick's book etc. would be in 3 - I volunteer to edit 3 as
: well.

The problem here, Jack, is that you didn't have your FAQs in hand,
specifically the FAQ called "How to create a new Usenet newsgroup"
which is posted in news.announce.newusers.
There are several other FAQs there, the reading of which reduces
one's being jumped upon. (you know, analogous to hiding 200-line
Feynman postings on the WELL)
From: bhoughto@sedona.intel.com (Blair P. Houghton)
Newsgroups: sci.physics
Subject: Re: Religion & Physics Don't Mix
Date: 8 Nov 1992 23:58:51 GMT
Organization: Intel Corp., Chandler, Arizona
NNTP-Posting-Host: alfalfa.intel.com

In article <1317@kepler1.rentec.com> andrew@rentec.com (Andrew Mullhaupt) writes:
>In article <1d9lk2INN73@agate.berkeley.edu> emarkp@soda.berkeley.edu (E. Mark Ping) writes:
>>In article <1d9fa5INNoc6@chnews.intel.com> bhoughto@sedona.intel.com (Blair P. Houghton) writes:
>>}The existence of physics belies the existence of the gods.
>>
>>Wait a second.  Do you think you can elaborate on that conclusion?
>
>Not only that, but can it get into Phys. Rev. Letters?

I'd much rather submit the idea that God exists to the
American Journal of Psychopathology, where they discuss
such delusions all the time.

				--Blair
				  "God hangs out with Santa Claus
				   and the Easter Bunny, two other
				   unprovables who don't have quite
				   the PR army that God does..."
From: cegtitd@prism.gatech.EDU (Tim Dodd)
Newsgroups: sci.physics
Subject: Re: Religion & Physics Don't Mix
Date: 11 Nov 92 19:05:37 GMT
Organization: Georgia Institute of Technology

In article <1992Nov11.175750.6605@spss.com| markrose@spss.com (Mark Rosenfelder) writes:
|In article <74353@hydra.gatech.EDU| cegtitd@prism.gatech.EDU (Tim Dodd) writes:
|(a very thoughtful article, with which I have only a few quibbles:)
  ^^^^^^^^^^^^^^^^^^^^^^^^^
       Thank you!

|There's nothing hard to understand, and nothing particularly religious,
|about faith.  Most of you probably believe that your Significant Other 
|isn't cheating on you.  Why?  Have you engaged private detectives?  Have
|you designed double-blind experiments to test your hypothesis?  No; you
|just trust them, and recognize that this kind of personal trust, rather than 
|scientific skepticism, is what's called for in a relationship.
|
|Religion simply asks for this kind of trust in one's god.  

But these are 2 very different kinds of "faith".  You *know* that your
S.O. exists, and the question as to whether or not he/she is cheating on
you is testable.

||On the other hand, honest theologians admit that God cannot be found through
||the use of reason.  A "leap of faith" is required to believe in God.  The
||act of taking this leap is mystical by definition, and cannot be rationally
||justified.
|
|Not all would agree.  In Catholic theology, for instance, it is asserted 
|that the existence of God can be proved by reason alone.  But "belief" in
|God is generally taken to require not just an acceptance of his existence,
|but trust and allegiance, and this is what cannot be based on reason alone.

I was not aware of this aspect of Catholicism.  Is this an official position
of the Church, or just something that appears in the writings of one or
more Catholic theologians?  In any case, it is not enough to assert that
the existence of God can be proved by reason.  One must *do* it, and so far
no one has.  Indeed it is not possible to do so.  If a rational proof of
God's existence were possible, just this possibility would be enough to
de-mystify God and render Him subject to physical law.

Tim
-- 
Tim Dodd, Research Scientist, Georgia Tech:  cegtitd@prism.gatech.edu
From: orca@StarConn.com (Sarah Emily Liberman)
Newsgroups: sci.physics
Subject: WANTED: Inexpensive CRC Handbook of Chemistry & Physics
Date: 12 Nov 92 21:18:32 GMT
Organization: Starnet-Public Access UNIX--Los Altos, CA  415-949-3133


Would anyone know how I may obtain copies of the CRC _Handbook of Chemistry
and Physics_ at a *discount*?  I would not mind if they are older editions,
just as long as they were printed within the last 10 years.

Please send your responses via e-mail only.

Many thanks!

-sarah emily liberman		e-mail:   orca@starconn.com
From: lnh@soliton.physics.arizona.edu (sometimes a Wombat)
Newsgroups: sci.physics
Subject: Re: Religion & Physics Don't Mix
Date: 8 Nov 92 16:04:29 GMT
Distribution: na
Organization: Society for the Appreciation of Janni Lee Simner

gene@aee.aee.com (Gene Kochanowsky) writes:
> If there is any complete nonsense here, it is that a person can be truely
> religious and scientific in his religion at the same time. It is absurd, 
> illogical and speaks volumes of misunderstanding on the part of that 
> person of what is the basis of both science and religion.

Tell that to Einstein.

(I do not know what religions you have been exposed to, but my
beckground in is a sect that specifically encourages constant
questioning and self-examination.)

(And there is no need to be so rude.)

	Larry "Appealing to historicity" Hammer
--

                         \   The work is rather too light, and bright,
LNH@physics.arizona.edu   \  and sparkling; it wants ... a long chapter
sometimes a Wombat         \ of solemn specious nonsense. -- Jane Austen
Newsgroups: sci.physics