HDTenEightyP/NetNews huggingface dataset:
From: bz223@cleveland.Freenet.Edu (Danny Guy Frezza)
Newsgroups: sci.physics
Subject: Transporter Technology
Date: 10 Oct 1992 19:01:41 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: bz223@cleveland.Freenet.Edu (Danny Guy Frezza)
NNTP-Posting-Host: hela.ins.cwru.edu


This may sound far out, but does anyone have any information on current
research in Transporter Technology, ie, the technology used on Star Trek?
It seems to me, that if the law of physics holds, ie, "matter cannot neither
be created nor destroyed, but transformed into energy of another form", that
this technology, although far out, is not impossible.
Please email if anyone has any current research on this topic or knows of it.
-- Thanks!
-- 

Dan Frezza
Internet: bz223@cleveland.Freenet.Edu

Newsgroups: sci.physics
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Re: SPACETIME AND BEYOND 1
Organization: MIT Department of Mathematics, Cambridge, MA
Date: Wed, 7 Oct 92 22:56:29 GMT

In article <1992Oct7.062757.19809@nuscc.nus.sg> matmcinn@nuscc.nus.sg (Mcinnes B T (Dr)) writes:
>sarfatti@well.sf.ca.us (Jack Sarfatti) writes:
>: 
>: The GOD(D) Drive of the most advanced Star Ships uses this psycho-geometric
>: mode of propulsion - requiring an Omega class bionic man at the helm...
>: 
>: Starting again from the cold mechanical computer-driven voice of Hawking:
>: Is Hawking a trance-receiver of telepatypes from the future super-
>: intelligence? Is Hawking a contactee of advanced extra-terrestrial
>: intelligence?
>				No.

Sarfatti, on the other hand, is a computerized database of theoretical
physics texts driven by an utterly crazed artificial intelligence.  Or
maybe just a fellow with a weird sense of humor - "Omega class bionic
man"??????
From: paul@mtnmath.UUCP (Paul Budnik)
Newsgroups: sci.physics
Subject: Re: Quantum reality silliness
Date: 12 Oct 92 03:28:12 GMT
Organization: Mountain Math Software, P. O. Box 2124, Saratoga. CA 95070

In article <1992Oct10.183406.6433@mnemosyne.cs.du.edu>, ddixon@nyx.cs.du.edu (David Dixon) writes:
>... 
> Which is all very well and good, but I would plead for application of
> Occam's razor once again.  Any mechanism which enables "communication"
> between two polarizers seems weirder and more ad hoc than the non-local
> or stochastic effects predicted by current QM.  Until someone does an
> experiment
>  showing that such a physical effect exists,
> then you might as well ascribe Aspect's result to non-commuting pixies.
>...

Everyone is entitled to their philosophical opinions. I would consider
assuming the universe to be nonlocal in the absence of experimental evidence
to be as a gross a violation of Ockham's razor as one can imagine.

We could argue about this until we were both blue in the face with little
to show for it. Science allows reasonable people to decide such issues,
but only if they keep straight what is philosophical opinion and what has
been observed `to be violated by TWENTY STANDARD DEVIATIONS!'.

I think quantum collapse is the transformation from one set of stable
dynamic structures to another. The conservation laws are structural
constraints on these transformations. These ideas are based on a class
of local deterministic models that at intuitive level have many of the
properties of quantum mechanical structures. In these models the
process of the decay of the excited state and the detection of the two
photons is a single process extended over many meters. The convergence of this
process to solutions consistent with the conservation laws is no more
strange then a swimming pool settling to a new level after one adds a
bucket of water. Information about the amount of water added is conveyed
throughout the swimming pool in a local and mechanistic way without
the aid of pixies.

These ideas are speculative and it would take a major effort to convert them
to a testable theory. This is not because these ideas are ill-defined.
The model can be completely specified at a time and distance scale that
is on the order of the planck length and time. Because the parts of this
theory that differ from quantum mechanics are not linear it is difficult to
understand how to convert a model at this scale to macroscopic experimental
predictions. The point is that a radical alternative such as this may
explain the effects observed in EPR experiments and much of the
other seeming strangeness of quantum mechanics in a local mechanistic way.
We will never now if we fail to look or close our minds to the possibility.

Paul Budnik
Newsgroups: sci.physics
From: ddixon@nyx.cs.du.edu (David Dixon)
Subject: Re: What does QM predict about *when* a photon traverses a polarizer?
X-Disclaimer: Nyx is a public access Unix system run by the University
	of Denver for the Denver community.  The University has neither
	control over nor responsibility for the opinions of users.
Organization: Nyx, Public Access Unix at U. of Denver Math/CS dept.
Date: Tue, 13 Oct 92 21:57:07 GMT

In article <315@mtnmath.UUCP> paul@mtnmath.UUCP (Paul Budnik) writes:
>The difficulty in testing Bell's inequality is in insuring that the
>correlated events have a space-like separation. These events are

Agreed.

>defined. But we are not detecting the particle at the polarizer. We
>are detecting it only after it has traversed the polarizer.
>I do not believe QM makes a clear prediction here. The particle must
>traverse the polarizer before it is detected and after it is emitted.
>QM cannot impose any additional constraints on this time without making
>assumptions about where the particle is between detections. This is
>not allowed in QM.

I'm not sure I understand what you're saying here.  Is there a problem with
solving the wave function on the "other" side of the polarizer?  This
strikes me as analogous to (though more complicated than) a potential
barrier problem.  Any condensed matter folks out there who know more about
light polarizers than I do want to expound on the physics of this situation?

					Dave
Newsgroups: sci.physics
From: zowie@daedalus.stanford.edu (Craig "Powderkeg" DeForest)
Subject: Black Holes, Hawking Radiation, and Entropy
Organization: Stanford Center for Space Science and Astrophysics
Distribution: sci
Date: 14 Oct 92 13:42:24


Yesterday, I was privileged to hear one of our local professors,
Leonard Susskind, speak about an inconsistency between quantum theory
and general relativity, that manifests in the thermodynamic treatment
of black holes.  Since sci.physics has been a forum for heated debate
on things like the EPR paradox, I thought this might be interesting to
the community at large.

I'll summarize his argument: 

One has to treat a black hole as though it had entropy proportional to
the surface area of its event horizon, to account for the myriad of
different ways any particular black hole could be assembled.  (eg if
you throw in an _Encyclopaedia_Britannica_, the information contained
therein is completely lost.)

However, several theorists (notably Hawking) have calculated that QED
predicts that any given black hole will emit black body radiation at a
particular temperature that is inversely proportional to its mass.
This means that, any black hole left to itself will eventually
evaporate, since mass/energy is carried away by the blackbody
radiation.  [though stellar black holes are huge enough, and thus have
a low enough temperature, that they would last many orders of
magnitude longer than the age of the universe.]

An important facet of Hawking's result is that, even in principle, one
cannot reconstruct any information from the outgoing blackbody
radiation, about how the black hole was assembled in the first place!
No quantum state information about the original mass is preserved.
[In contrast, if one were to heat, say, a block of coal with a
modulated laser beam, the outgoing blackbody radiation would, in the
form of subtle phase differences, carry all of the incoming
information in the laser beam.]

The problem arises thus: one may consider the action of the black hole
as a scattering experiment.  We start with a myriad of incoming
particles, say several trillion copies of the _Encyclopaedia_
_Britannica_ [and maybe a star or two], and end with a heck of a lot
of diverging photons, with the photon energy in each expanding
spherical shell distributed according to the blackbody radiation law
for the temperature of the B.H. when that shell was emitted.

The problem is that quantum mechanics requires the operator of this
scattering experiment to be unitary, ie invertible.  In principle (if
not in practice), we ought to be able to time-reverse the process,
writing down a wave equation for many converging spherical shells of
photons to produce a small B.H., which would then grow and eventually
explode into a large collection of Encyclopaedias and a star or two.

Hawking's claim, according to Dr. Susskind, is that such a time
reversal is impossible, as the information in the B.H. ingredients is
totally lost.  Thus, something is fishy between general relativity and
quantum mechanics.

Chew on that!
--
Craig DeForest -- astrophysicist for hire: (415) 723-3216         1-line sig!
From: sasrbk@banana.unx.sas.com (Bart Killam)
Newsgroups: sci.physics
Subject: Question on Young's Equation
Keywords: interfacial tension, wetting, nonwetting
Date: 8 Oct 92 14:55:52 GMT
Organization: SAS Institute Inc.
Originator: sasrbk@banana.unx.sas.com



I am having a problem understanding Young's
equation, an equation relating the connecting
angle of an air-water interface (in a air-water-
solid interace) with the interfacial tensions.
The equations seems counter-intuitive, and seems
to violate the principle of least action.

I am reviewing a text (Quantitative Hydrogeology, 
de Marsily) that discusses wetting/non-wetting
fluids in a air-water-solid interface. In a 
diagram (Fig. 2.12, p 28) of the interface, the
solid boundary is horizonal, with the water forming
a droplet on top. This is probably a common diagram
shown in any soil physics or physical chemistry text. 

The angle of the air-water interface is measured 
through the water. If the angle < 90 deg. the fluid
is "wetting". This is easy to see; as the angle 
approaches 0 deg., the drop spreads out over the
entire surface. Similarly, if the angle > 90 deg. 
the fluid is "non-wetting". As the angle approaches
180 deg., the droplet beads up to where only a point
is touching the solid. Again, easy to visualize.

 However:

 Young's Equation:


   cos(theta)= (sigma_s_a - sigma_s_w)/sigma_a_w

where  

  theta = the connecting angle

  sigma_s_a = interfacial energy between the solid-air
              (the energy required to separate a unit
               area of air-solid interface)

  sigma_s_w = interfacial energy between the solid-water

  sigma_a_w = interfacial energy between the air-water

Suppose (using J/m**2 or any convenient units)

  sigma_s_a = 1, sigma_s_w = 2 , sigma_a_w = 1

Since it take twice the amount of energy to peel
a unit area of solid-water apart compared to
solid-air, or air-solid, it would seem that the
system would seek to minimize its energy by
spreading the water over the entire surface
(theta-0). However, these values give theta=180,
where the water is only touching at a single
point. This seems a much higher energy state.

What is wrong with my reasoning. Thank you
for any help on this.

--- Bart Killam,  SAS Institute Inc. 
Newsgroups: sci.physics,sci.math,soc.men,soc.women
From: bhv@areaplg2.corp.mot.com (Bronis Vidugiris)
Subject: Re: Mattel on women
Organization: Motorola, CCR&D, CORP, Schaumburg, IL
Date: Wed, 7 Oct 1992 17:34:14 GMT
Keywords: Targetting females once again.

In article <267843@peregrine.peregrine.com> dmi@peregrine (Dean Inada) writes:
)In article <1992Oct6.224326.3834@lmpsbbs.comm.mot.com> bhv@areaplg2.corp.mot.com (Bronis Vidugiris) writes:

)>I do think it would be quite reasonable to listen to what your kid's Barbie
)>says, and seek a replacement for it if you don't like what it's saying
)>strongly enough - something strikes me as being a bit 'wrong' about
)>trying to 'censor' all Barbies everywhere.
)>
)Censor?  Hmm, I think I'll have to agree...
)We shouldn't let Mattel 'censor' the counter-view that 
)hard subjects like math can be fulfilling and important
)by making Barbie deliver their 'Math Phobic' view exclusively.

Hmm - you know, I would be more sympathetic to a view that did ask Mattel
to say some nice things about math than one which simply says 'Don't say
math is hard', which is really rather 'reactive'.

Unfortunately, though I really *do* like math, I'm having a hard time
imagining something that a 'Barbie' could reasonably say that would be
supportive of it :-( :-(.

'Math will make you rich'?  Nope - besides it's not true.  'Math is very
useful for understanding science and the world'?  Yep, but that's not a
Barbie sort of thing to say.  'Math will get you lots of boys/dates'?  -
Nope, sorry :-).  "Math is intellectually developing"?  True, but from
Barbie?  I suppose we could have her do a math-cheerleading song :-) :-)
[we acually had one of those at college - it went something like "Tangent,
secant, cosine, sine - 3.14159 e^x e^y e^-pi."]  However, that does seem too
advanced for Barbie :-(.

Any ideas for nice things a 'Barbie' _could_ actually say about math?  How
about some other dolls - I suppose it could maybe work for an astronaut doll.
Seems a bit far-out though.

Anyway, I think it'll take a really major effort to improve the view the
average person has of math and science in this country - merely 'coming down'
on Barbie isn't going to solve that problem.
From: bweiner@ruhets.rutgers.edu (Benjamin Weiner)
Newsgroups: sci.physics
Subject: Re: Wavefunction of the universe calculated!!!
Date: 13 Oct 92 22:07:19 GMT
Organization: Rutgers Univ., New Brunswick, N.J.

John Baez writes:
> [re Maharishi equations]
>By the way, I believe that it was a Lagrangian for a supersymmetric
>field theory that real physicists have studied, but with the individual
>terms labelled with terms like "truth," "harmony," "consciousness".

Not truth, beauty, charm, strangeness, up, down?
Oh well, I guess those last two aren't spiritual enough anyway.  BTW,
the Maharishi will never get anywhere on the Theory of Everything, if
only because Maharishi International University has a strict dress
code (suits & ties, no jeans, etc.) and there can't be more than one
or two particle physicists who will put up with that.  (I am not
making this up.  Get some of their recruitment literature - it's a
gas.)
Newsgroups: sci.physics,sci.math
From: pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt)
Subject: Re: How do you draw a straight line?
Organization: Computer Science Department,  Stanford University.
Date: Wed, 14 Oct 1992 07:26:03 GMT

In article <1992Oct14.070415.18973@CSD-NewsHost.Stanford.EDU> pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt) writes:
>as an ideal gear (slightly irregular motion as the teeth slide over
>each other) or belt-drive (same problem as the chalk-line solution:

Oops, I should have worded that without the offending word "slide",
since there exists a tooth shape for which the teeth roll without
sliding.  The "irregular motion" I had in mind *should* occur even in
this case, as a result of that shape (or any other shape, sliding or
not) not keeping the angular velocity of the gears perfectly
matched---anyone know for sure?

For the limiting case of infinitely many infinitesimal teeth the
angular velocity *is* matched.  But this is the case of a friction
drive, for which one expects some slippage in any practical
realization.
-- 
Vaughan Pratt   pratt@cs.Stanford.EDU     exp(n pi sqrt(163)/3) for n=1..30
From: lnh@soliton.physics.arizona.edu (sometimes a Wombat)
Newsgroups: sci.physics
Subject: Re: TIME HAS INERTIA, ALTERING THE EARTH'S TILT ... Reply to: WOMBAT
Date: 9 Oct 92 15:22:32 GMT
Followup-To: alt.prose.d
Distribution: na
Organization: Society for the Appreciation of Janni Lee Simner

Whoops, that's me.

Alexander Abian writes:
>    The state of any object (animate or inanimate) at any moment on any 
>planet of our Solar System is inextricably related to the setup of our
>Solar System at that moment.  [etc.]

RFOL!

This gave me such a belly laugh, once I realized it was a joke.  I
humbly suggest that, in the future, you might make your satire slightly
clearer -- perhaps by making the views expounded by your net.persona
more extreme?  Not sure.  

> Stop asking trivial questions "how are you going to do"  etc. etc. 
> (the idea is first - the action will follow).   

"Expect poison from standing water ... Sooner murder an infant in its
cradle than nurse unacted desires."
		-- William Blake

Here's a possible place -- if you give the speaker an actual
*mechanism* for all this cosmic engineering, some claimed way of doing
it, that might help.  But then, I tend to over-critique towards clarity
when ambiguity could be better.  I think the group for prose criticism
is alt.prose and alt.prose.d -- you maybe could ask there for reviews.
Or not, if you're confident of your net.voice.

On a more personal note:

>  Mr.  Wombat, ...

I beg your pardon, but I am only SOMETIMES a Wombat.  And never in
sci.physics.  The academic community shows a distressing bias against 
the hiring and advancement of marsupials.

>  As far as cranks are concerned, many people consider Copernicus, Galileo,
>Newton and Einstein as being cranks, in fact, quite obnoxious, arrogant,
>aggressive and throat-cutting  megalomaniac nasty cranks.  

Well, Newton WAS obnoxious, arrogant, aggressive, throat-cutting,
megalomaniacal, and nasty, but he was only sometimes a Crank.  I boggle
at applying megalomaniacal to Einstein, tho'.

	Larry "sometimes Cranky" Hammer

--

LNH@physics.arizona.edu     \   One like a wombat prowled obtuse
GEnie: L.HAMMER2             \  and furry  -- Christina Rossetti
Newsgroups: sci.physics
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Wavefunction of the universe calculated!!!
Organization: MIT Department of Mathematics, Cambridge, MA
Date: Thu, 8 Oct 92 19:39:16 GMT

Yes, folks, you heard it here first, on that authoritative font of all
wisdom, sci.physics.  The wave function of the universe has been
calculated:

Paper (*cross-listing*): gr-qc/9210003
From: "H. Ueda (YITP, Uji)" <ueda@yisun1.yukawa.kyoto-u.ac.jp>
Date: Wed, 07 Oct 92 22:30:06 +0900
     
The Wave Function of the Universe by the New Euclidean Path-integral
Approach
in Quantum Cosmology, Atushi Ishikawa and Haruhiko Ueda, 11 pages,
OU-HET 169
\\
The wave function of the universe is evaluated by using
the Euclidean path integral approach.


Well, then it goes on to reveal that they cut a few corners:

As is well known, the real Euclidean path integral diverges
because the Einstein-Hilbert action is not positive definite.
In order to obtain a finite wave function, we propose a new
regularization method and calculate the wave function of the Friedmann-
Robertson-Walker type minisuperspace model.
We then consider a homogeneous but anisotropic type minisuperspace
model, which is known as the Bianchi type I model.
The physical meaning of the wave function by this new regularization
method is also examined.

(A "minisuperspace model" is one in which only finitely many
gravitational degrees of freedom are kept - sort of like how Lorenz
got his equations by brutally truncating the Navier-Stokes equations
down to the first few Fourier components.  Oh well, it started out
sounding so ambitious!)
From: naturman@uctvax.uct.ac.za
Newsgroups: sci.physics
Subject: Non-locality Joke
Date: 12 Oct 92 14:00:07 +0200
Keywords: non-locality
Organization: University of Cape Town

If the rate at which physics papers are being published continues to increase,
physics journals will soon be filling library shelves faster than the speed
of light.

Relativity theorists say that this does not violate Einsteinian Locality since
no useful information is being tansmitted.

 
(Don't get all excited this is just a joke.)

--
_______________________________________________________________________________
|                                                                             |
| Fluffy, the Quantum Kitty                                                   |
| c/o Colin Naturman             "`All right,' said the Cat; and this time it |
| naturman@uctvax.uct.ac.za        vanished quite slowly, beginning with the  |
|                                  end of the tail and ending with the grin,  |
|                                  which remained some time after the rest of |
|                                  it had gone."                              |
|                                                                             |
|                          Lewis Carroll,  Alice's Adventures in Wonderland   |
|_____________________________________________________________________________|
From: carlip@landau.ucdavis.edu (Steve Carlip)
Newsgroups: sci.physics
Subject: Re:  Simple observation about Quantum Kitty Cats
Date: 7 Oct 92 18:55:34 GMT
Organization: Physics, UC Davis

In article <1992Oct5.171817.7596@oracorp.com> daryl@oracorp.com (Daryl McCullough) writes:

[...]
>Your point would seem to be that the situation rapidly changes
>from being described by the state
>
>     (|alive> + |dead>) x |?>
>
>to being described by the state
>
>     (|alive> x |ALIVE>) + (|dead> x |DEAD>)
>
>There is still a superposition, but it doesn't only involve the state
>of the cat.[...] 
>the total state of the world described above can just as easily
>be written as
>
>     1/2 (|alive> + |dead>) x (|ALIVE> + |DEAD>) +
>     1/2 (|alive> - |dead>) x (|ALIVE> - |DEAD>)
>
>What makes the states |alive> and |dead> a better or more accurate way
>to describe things than |alive> +/- |dead>? The formalism of quantum
>mechanics doesn't give an answer. It's possible that a preferred basis
>is derivable from statistical mechanics (since such preferred bases
>only come in with macroscopic measurements), but I have never seen it
>done.

This is what is called the problem of finding the ``pointer basis''
in approaches like the many-world or relative state interpretations.
I'm not an expert on this subject, but it is a big part of what
Gell-Mann and Hartle have been working on in their reinterpretation
of the Everett relative state interpretation.  

Gell-Mann and Hartle argue that the existence of a preferred basis 
describing ``classical'' behavior is really a question of quantum
cosmology, in some sense --- it depends on the initial conditions
for the wave function of the universe.  You can have wave functions
in which classical physics emerges as a good approximation, for
which such a preferred basis exists, and others for which this doesn't 
happen.  They suggest that a crucial test of any proposal for a set
of initial conditions, such as Hawking's  now famous ``no boundary'' 
proposal, is whether a suitable preferred basis emerges.   

One reference is J.B. Hartle, ``Classical physics and Hamiltonian 
quantum mechanics as relics of the big bang,'' Physica Scripta 36
(1991) 228.  (I haven't actually read this article, but I've heard
talks by Hartle...)

Steve Carlip
carlip@dirac.ucdavis.edu