HDTenEightyP/NetNews huggingface dataset:
From: mw@irfu.se (Mattias Waldenvik)
Subject: Re: Conductivity of air
Date: Wed, 16 Dec 1992 14:20:53 GMT
Organization: Swedish Institute of Space Physics, Uppsala, Sweden

In article <1416@kepler1.rentec.com> andrew@rentec.com (Andrew Mullhaupt) writes:
>If I shoot UV light through air will there be an increase in conductivity
>along the path of the light? Enough to measure? If so, how might I figure
>out the resistance of the path?
>
>Any references or pointers would be appreciated.
>
>Thanks in Advance,
>Andrew Mullhaupt

	Well, in the spirit of Ben Franklin you could wait for the
	next thunderstorm. Make sure you wear rubber boots though. :-)

					Mattias
Newsgroups: sci.physics,alt.sci.physics.new-theories
From: daryl@oracorp.com (Daryl McCullough)
Subject: Re: QM non-causal?
Organization: ORA Corporation
Date: Thu, 17 Dec 1992 20:44:46 GMT

jbaez@riesz.mit.edu (John C. Baez) writes:

>Not everyone finds Bell's result disturbing. Bell's inequality is
>derived in the framework of classical mechanics, so the fact that it is
>violated in the framework of quantum mechanics is just one of millions
>of ways in which quantum mechanics differs from classical mechanics.
>This is only disturbing if in some sense you still have classical
>intuitions about how the world works.  While people can take Bell's
>result in different ways (Giles' point), it seems to me the safest
>conclusion about "what fundamental concept is wrong" is that CLASSICAL
>MECHANICS IS WRONG.  This, of course, is no longer news.

I disagree that "Bell's inequality is derived in the framework of
classical mechanics". Nothing in the derivation mentions *mechanics*
at all!

What I would say is that Bell's inequality is derived in the framework
of classical probability theory, and thus if anything it shows that
the assumptions of classical probability theory are wrong.

In particular, a simplified version of Bell's inequality is due to the
observation that:

     P(A and B) + P(not-B and C) >= P(A and C)

In EPR-like experiments, we can get what seems to be a violation of
this rule of probabilities. (I say "seems" because of course
experimental results are subject to different interpretations.)

Daryl McCullough
ORA Corp.
Ithaca, NY
Newsgroups: sci.physics
From: Leigh Palmer <palmer@sfu.ca>
Subject: Re: Metals in liquid Nitrogen !!
X-Xxmessage-Id: <A74FC273D5011C15@rs10-annex3.sfu.ca>
X-Xxdate: Sat, 12 Dec 92 00:23:15 GMT
Organization: Simon Fraser University
X-Useragent: Nuntius v1.1.1d13
Date: Sun, 13 Dec 1992 00:22:36 GMT

In article <1992Dec12.015936.10957@nuscc.nus.sg> Brett McInnes,
matmcinn@nuscc.nus.sg writes:
>ps. Pennies are not made of copper. They are mostly zinc.

Not in Canada, where the question was asked. Are U.S. pennies really
mostly zinc? I knew they were in 1943, but those looked like zinc. U.S.
pennies look like copper to the casual observer.

Leigh
Newsgroups: sci.physics
From: jarleb@diana.uio.no (Jarle Brinchmann)
Subject: Re: Can space-time intersect itself?
Reply-To: jarleb@diana.uio.no (Jarle Brinchmann)
Organization: Institute for Theoretical Astrophysics
Date: Thu, 17 Dec 1992 12:23:56 GMT


In article <1992Dec16.120557.22262@nuscc.nus.sg>, scip1061@nuscc.nus.sg (Marc Paul Jozef) writes:
|>Newsgroups: sci.physics
|>From: scip1061@nuscc.nus.sg (Marc Paul Jozef)
|>Subject: Re: Can space-time intersect itself?
|>
|>: G.Joly@cs.ucl.ac.uk (Gordon Joly) writes:
|>: 
|>: The answer probably lies in superstring theory...
|>
|>
|>    Certainly not.
|>

Well, you might be right about the answer, but in superstring theory
you can get non-trivial topologies in the curled up dimensions, and
that could suggest that our "usual" space could have a non-trivial 
topology. Or am I just completely lost ?


			Jarle.

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

Newsgroups: sci.physics
From: daryl@oracorp.com (Daryl McCullough)
Subject: Re: FTL communication in SR does not violate causality
Organization: ORA Corporation
Date: Sat, 12 Dec 1992 21:53:43 GMT

markc@smsc.sony.com (Mark Corscadden) writes:

>The mathematics of Special Relativity, when one allows for some general
>faster-than-light communication mechanism, does not create causality
>problems.

[stuff deleted]

>Here is an outline of a proof that a causality-violating chain cannot be
>found with this corrected formulation of the meaning of FTLC.  Choose a
>preferred reference frame...
>
>Now define the relation "caused" on the set of all events by saying that
>event A caused event B if and only if B has a time coordinate greater than
>A's in the preferred reference frame.  This relation is transitive, that
>is, if A caused B and B caused C then A caused C; and it is not reflexive,
>namely, there is no A such that A caused A (itself).  Yet it provides a
>model that satisfies both SR and the general FTLC capability described
>above, where E is chosen as described above.  The existence of this model
>shows that you can't produce a causality-violating chain based only on
>the mathematics of SR and the assumption of general FTLC, since your
>argument would produce a chain in this model, which has no such chain.

I agree that this is perfectly consistent. However, I would not say
that your model is consistent with Special Relativity, I would instead
say that your model is consistent with the Lorentz Transformations. I
consider to be an assumption of SR that the laws of physics are the
same in all inertial reference frames. With your "preferred reference
frame", you are violating this assumption.

Daryl McCullough
ORA Corp.
Ithaca, NY
From: emarkp@soda.berkeley.edu (E. Mark Ping)
Newsgroups: sci.physics
Subject: Believe it or not, Abian, you are not the messiah of Physics.
Date: 13 Dec 1992 23:05:29 GMT
Organization: U.C. Berkeley, CS Undergraduate Association
NNTP-Posting-Host: soda.berkeley.edu

In article <Bz7z5H.9Bn@news.iastate.edu> abian@iastate.edu (Alexander Abian) writes:
}
}
}                                       12-13-92
}   
}Dear Mr. Riemsrs,
}
}You write:
}

[mucho stuff deleted]

}     My answer is:
}
}     THE  FEELING IS MUTUAL
}
}With love                                       Alexander Abian

  Boy can Abian offend or what?  The title of that last post was:

 TIME HAS INERTIA -  OBEY ANF FOLLOW  ALEXANDER ABIAN
					 ^^^ -- I assume that's supposed to be 'AND'

  Hello?  I'm waiting now for you to proclaim your divinity.

------------
E. Mark Ping
emarkp@soda.Berkeley.EDU

  "Stand aside, I take large steps."  --Michael Dorn
  (I _know_ he didn't say it first, he just said it well!!!!)
  "Say, that's a nice bike."          --Cyberdyne Systems T-1000
  "Pituita es."                       --Unknown Latin Scholar
From: dseeman@novell.com (Daniel Seeman)
Newsgroups: sci.physics
Subject: Re: Special relativity is SOOO irritating!
Date: 16 Dec 92 19:15:20 GMT
Distribution: sci
Organization: Novell Inc., San Jose, Califonia

In article <D91ANDIV.92Dec15234743@astmatix.IDA.LiU.SE> d91andiv@IDA.LiU.SE (Anders Ivner) writes:
>This question has been puzzling me for awhile, but it should not
>cause much trouble to you guys. (I hope.) (My scientific English
>is not as good as it should be, so pardon any errors...)
>
>Consider a staff, one meter long. Now, given the speed v it 'shrinks'
>to half a meter. We then have a wall, and an easily controllable
>hatch placed .75 meters from the wall. The staff passes through the 
>hatch, and we close the hatch behind it (BEFORE it hits the wall!)
>The staff hits the wall, without being deformed (somewhat unrealistic!),
>and since its speed now changes to 0 it is now fully 1 meters long.
>What the **** happens????
>
>Anders, who likes to torture himself with questions he can't answer.

I just realized that your refernce in the problem above is that of the wall and
hatch since it is the stick that looks smaller.  In this case, due to the
acceleration the stick undergoes when it hits the wall, you would see the end of
the stick poke back through the hatch.  And when all is said and done (this
would happen *very* quickly) it would look as though the stick had been launched
through the hatch from the wall side.

I am just trying to follow logic that I have in my head.  I would like to know
if this explanation is even remotely close.  So, to all the rest of you, please
let me know if this is correct or not...;-)

Thanks,
dks
Xref: sparky sci.physics:21113 sci.math:16856
From: columbus@strident.think.com (Michael Weiss)
Newsgroups: sci.physics,sci.math
Subject: Re: Bayes' theorem and QM
Date: 14 Dec 92 09:56:16
Organization: Thinking Machines Corporation, Cambridge MA, USA
	<1992Dec11.220139.14066@newshost.lanl.gov>
	<1992Dec13.204233.10835@galois.mit.edu>
	<1992Dec14.003452.12884@galois.mit.edu>
	<SRCTRAN.92Dec13221623@world.std.com>
NNTP-Posting-Host: strident.think.com
In-reply-to: srctran@world.std.com's message of 14 Dec 92 03:16:23 GMT

In article <SRCTRAN.92Dec13221623@world.std.com> srctran@world.std.com
(Gregory Aharonian) writes: 

   Speaking of Bayes Theorem, one theorem I never see mentioned in many of
   these discussions, and I am almost afraid to mention it (since it can
   spawn many pseudo theories) is a theorem due to Gregory Chaitin at IBM,
   who proves that if you accept the basic properties of Integers, then it
   follows (in a very pretty argument) that statements about reality are 
   all probabilistic, that any theory that uses the integers implicitly
   is bringing in randomness  (or that's how I interpret his work).

   One could argue that some of the probability that comes into play with
   quantum theories comes from the fact that physicists use integers to
   experiment and predict, that there is an unstated axiom in physics that
   things are probabilistic.

   I know I am mishandling his ideas greatly, and would appreciate it if
   some of the theorists could read his work and see if there is any relevance
   to the axioms of physics.  If nothing else, his papers are great reading.

You are indeed "mishandling his ideas", more or less like saying "Goedel
proved no theory can be complete", or "Heisenberg showed everything is
uncertain".

Chaitin showed that there is a real number Omega between 0 and 1 whose
binary expansion satisfies two properties:

(1) It can be defined arithmetically.  That is, the proposition "the n-th
    bit of Omega's binary expansion is 1" is equivalent to saying "G(n) is
    true for the integers", where G is a formula with one free variable in
    the language of Peano arithmetic.

(2) Omega is Solomonoff-Kolmogorof-Chaitin random.  The definition of this
    notion is somewhat technical.  VERY ROUGHLY speaking, Omega will pass any
    sequence of statistical tests that can be posed by a Turing machine.
    However, there are plenty of pitfalls on the path from this intuitive
    notion to a precise mathematical concept.  (Consult Chaitin's book, or
    the entry in the Handbook of Computer Science on algorithmic
    information theory (I forget the authors).  I also have notes in LaTeX
    that people are welcome to.)

I agree it would be nice if a close connection could be forged between
Chaitin's ideas and the foundations of QM.  At the moment though such ideas
are pure speculation; no one (to my knowledge) has shown how this can be
done.


Newsgroups: sci.physics
From: wdh@faron.mitre.org (Dale Hall)
Subject: Re: Can space-time intersect itself?
Followup-To: sci.physics
Summary: be careful with embedding theorems
Keywords: embedding, isometry
Organization: Research Computer Facility, MITRE Corporation, Bedford, MA
Distribution: net
Date: Mon, 14 Dec 1992 21:14:27 GMT

In article <398@moene.indiv.nluug.nl> toon@moene.indiv.nluug.nl (Toon
			Moene) writes: 
>In article <1992Dec2.232639.13222@galois.mit.edu> jbaez@riesz.mit.edu
>(John C. Baez) writes:
>> In article <1992Dec2.014924.8076@netcom.com> raicu@netcom.com (Eugen  
>Raicu) writes:
>> >In principle, can there be any mass distribution that would result in a
>> >space-time which intersects itself? 
>> 
>> Not as far as I can tell, if I understand the question.  The point is
>> that spacetime is not embedded in some higher-dimensional space so it
>> can't "bump into itself".  This is precisely why it's nice to have an
>> intrinsic definition of manifolds, by the way!
>
>Now that's interesting - I'm sure I remember from my Differential Geometry  
>course that ANY manifold can be embedded in Rn. A five minutes worth of  
>flapping through the pages of my DG book* tells me that I have to modify  
>this to: ANY manifold that has a COUNTABLE base (so-called seperable  
>manifold).

	This is of course true, but for embedding results you require
	a certain number of "extra dimensions".  

	For plain-old smooth embeddings a manifold of dimension n can
	be embedded in R^(2n+1). (Actually if n>2 it's R^(2n) by
	something called the Whitney trick.  But then, there are only
	so many 2-dimensional manifolds [besides the 2-sphere, it's
	just connected sums of tori & projective planes], and they all 
	embed into R^4, so R^(2n) works for every compact n-manifold.)

	However, if you're married to the notion of a particular
	Riemannian metric, then the best you can do is R^(n^2+10n+3),
	according to Gromov ("Partial Differential Relations").
	Notice the quadratic in the dimension: it tells you that to
	have all the luxury of home, it'll cost you plenty.  Who
	woulda thunka needing R^42 for a dumbole M^3?  If the version
	for Lorentz metrics were true, you would be worrying about
	R^59 to hold spacetime.  Damb.

	The fact that manifolds can be embedded in Euclidean space
	appears (to me) to be over-used and under-understood by people
	in general.  While embedding can be useful and fun, it does
	carry a certain price, in this example, in terms of additional
	coordinates that may appear.  Whether this additional load of
	scientific baggage constitutes a good investment is not an
	obvious question.


Newsgroups: sci.physics,alt.sci.physics.new-theories
From: mkaufman@mcs.kent.edu (Michael Kaufman)
Subject: re:Time Has Inertia		
Organization: Kent State University
Date: Fri, 18 Dec 1992 21:08:11 GMT

	Ok, I've been waiting patiently by, listenig(reading) all the 
great stuff that's on here.  Why?  Because I like physics and am a physics
major.  yes I AM a sadist, but that's besides the question.  
	I've really been bugged by teh "TIME HAS INERTIA" thread.  Basically,
  I DON'T GET IT!!!!!!  I'm a multi-dimensional nut, so when i saw something 
related to the fourth dimension, I read it.... and was confused!
All I've gotten from this thread is Aristotlean and other philosophical
theories, some of which have been disproven for years.  
	If someone could remember, please tell me the first Abian(sp?)
message.  Does it regard inertia and time at all, or is it just blow off?
If it does, please re-post it so I could at least inspect it.
If anyone would like to get off this flame thread and talk about a real 
subject, time and it's implication/ramifications, then I'll be happy
to post more.

Mike Kaufman
mkaufman@mcs.kent.edu
Newsgroups: sci.physics,alt.sci.physics.new-theories
From: sarfatti@well.sf.ca.us (Jack Sarfatti)
Subject: Mind, Matter & QM re: "Gentle Action" by Peat.
Organization: Whole Earth 'Lectronic Link
Date: Sun, 13 Dec 1992 03:39:09 GMT


Mind, Matter & Quantum Connection 4

More comments on Peat's article in the Mind Matter Conference proceedings
edited by Dr. Beverley Rubik of Temple University Center for Fronteir
Sciences. I am following up on Dr. Rubik's request to review the book - and
am doing so in a sequence of short remarks.

p.202 0n "Gentle Action"
"... a highly complex system in which its individual phases are subject to
fine adjustments.  By making a series of small adjustments globally across
the system is becomes possible to lock these phases together so that the
whole system becomes involved cooperatively in some new activity. Such a
system may be quite resistant to any local, forceful intervention; however,
tiny changes that are made in a co-operative or non-local way can result in
entirely new behavior."

This is a very nicely written image and very enticing and I hope it is true
- it would help to see a simple math model of it. Should we think
classically of a distribution of systems across space at a fixed time with
a field of little phasors? Or should we think quantum mechanically in
Hilbert space. If we have several systems then we have an entangled sum of
products of kets one for each system. So take the photon pair case in which
we start with

|1,2> = (1/sqrt2)[|1+>|2+> + |1->|2->]

consider, for example

|1,2> -> |1,2>' = (1/sqrt2)[e^i&|1+>|2+> + |1->|2->]

where & is a relative phase - but it is not a phase attached to either
photon 1 or photon 2.

Just what kind of math model would illustrate Peat's verbal picture? I am
at a loss and would like to hear from Peat.





Newsgroups: sci.physics
From: y41@aix320c.urz.uni-heidelberg.de (Jeffrey Hazelwood)
Subject: Just the FAQ's please!!
Organization: University of Heidelberg, Germany
Date: Thu, 17 Dec 92 16:28:15 GMT


Gibt es hier ein FAQ oder was?  

-------------------------------------------------------------------------------
SMAIL: Jeffrey T. Hazelwood                    Universitaet Heidelberg
       Ploeck 61/106                            Heidelberg, Germany
       6900 Heidelberg, Germany                  
EMAIL: y41@ix.urz.uni-heidelberg.de            "Doch, Gott wuerfelt!" 
-------------------------------------------------------------------------------
Newsgroups: sci.physics
Subject: Re: FTL communication in SR does not violate causality
From: mcirvin@husc8.harvard.edu (Matt McIrvin)
Date: 18 Dec 92 23:33:24 GMT
Keywords: FTL SR causality Special Relativity

markc@smsc.sony.com (Mark Corscadden) writes:

>In article <mcirvin.724046110@husc8> mcirvin@husc8.harvard.edu (Matt McIrvin) writes:
>>If you just examine E1, E2, and E, there's no trouble.  But consider this:
>>
>>Suppose that there is apparatus at rest in O2's frame that is just like
>>O1's, and vice versa.  O2 can set up events F1 and F2 which are both at
>>the origin of O2's spatial coordinates; F1 follows E and F2 follows F1,
>>according to O2's time coordinate.  F1 causes event F which is at the
>>origin of O1's spatial coordinates, which in turn causes F2, all of this
>>reckoned using O2's time coordinate.  This must be possible if SR
>>applies and the apparatus works everywhere. 

>Okay so far, except that the phrase "reckoned using O2's time
>coordinate" seems not wrong but misleading.  F1 causes F causes F2
>is not reckoned in relation to any time coordinate; causality is an
>objective relation that holds in all reference frames regardless of
>time coordinates.  It is a bit odd that the time coordinate of F1 can
>follow (i.e. be greater than) the time coordinate of F (in O2's frame)
>even though F1 caused F, which was why I was careful to say just what
>FTLC entails.

I was going to agree that this is a fine way to talk about things, but
now I think we're talking about two different physical situations.
I misunderstood your post.

I was picturing a situation in which F follows F1 and F2 follows F
*in O2's frame*  if F1 causes F causes F2.  You seem to be defining 
"F1 causes F causes F2" as a situation in which F happens to follow
F1 and precede F2 in O1's frame.

In that case, F indeed cannot precede E1 if the chain of causation
is such.  But such a model does *not* obey special relativity.
There is a preferred frame, namely the frame in which causation
corresponds to the ordering of time coordinates.  The physics of
this model allows messages to be sent faster than light as long as
the time coordinates of the associated events are in order in
the preferred frame.  Physicists moving at different speeds could
do local experiments to distinguish their frames from each other;
the laws of physics would not be the same in all inertial frames.

Nevertheless, such a situation is certainly *possible.*  As I just
pointed out in my response to Tom van Flandern's post, it can
be consistent with *all* the current evidence in favor of special
relativity; you just have to assume that the SR-violating mechanism 
by which this communication occurs hasn't been discovered yet.
There would be nothing to keep all the rest of the stuff in the
world from obeying SR.
-- 
Matt McIrvin
Newsgroups: sci.physics
From: godzilla@maths.tcd.ie (Frank O'Connor)
Subject: Re: (A1) EXPLAINS THE PHYSICS from particle to Galaxies
Keywords: (A1)                                           12-11-92
Organization: Dept. of Maths, Trinity College, Dublin, Ireland.
Date: Tue, 15 Dec 1992 11:17:19 GMT

Two books to be found under Abian's bed:

(1) The Hitch-hikers Guide to the Galaxy

'Some people see the existence of the Babel fish as proof
of the non-existence of God.'

(2) Red Dragon

Francis Dolarhyde was becoming powerful now. He watched the video,
over and over. Soon this family would bow to the logic of (A3).
He would slit their throats- reaction to provocation - and then
they would know the mystery of (A3). He would share enlightment
with them. He was- the GREAT ABIAN. With love.

Frank O'Connor.
------------------------------------------------------------------------------
Frank D. O'Connor               3nd Year Physics        Trinity College Dublin
<oconnorf@unix1.tcd.ie>     <godzilla@maths.tcd.ie>     <oconnorf@vax1.tcd.ie>

There is nothing you can think of that nobody would enjoy.
------------------------------------------------------------------------------
From: murphy@npri6.npri.com (David P. Murphy)
Newsgroups: sci.physics
Subject: (A3) IS VAPOR
Date: 14 Dec 92 17:15:35 GMT
Distribution: world
Organization: NPRI, Alexandria VA


 >    Physicists who reject (A3), they reject it because they are fanatically
 >maintaining their indoctrination as to what Physics and Science is. THEY
 >REJECT (A3) BECAUSE THEIR REJECTION OF (A3) MAKES THEM FEEL SECURE.

i see.  but _you_ are not fanatically maintaining _your_ position, right?

 >    Physicists who accept (and believe me there are some - and their number
 >is growing) (A3), they accept it because the explanation of some phenomena 
 >by invoking (A3) is much more convincing and rational.  THEY ACCEPT (A3) 
 >BECAUSE THEIR ACCEPTANCE OF (A3) MAKES THEM FEEL SECURE
 >
 >abian@iastate.edu (Alexander Abian)

well, which is it?  do they accept it because it is rational or because
it makes them feel secure?  if the latter, you have proved nothing.
if the former, why do the "rejecting" physicists not find it rational?

>why does water dilute ink? You go and ask the chemist,
>his /her first answer most probably will be "ask a physicist".

obviously you have not actually _asked_ a chemist.

>   TIME HAS INERTIA IS BECOMING ACCEPTED. THIS NOBEL-PRIZE WINNING
>   ASSERTION [blah blah blah]

not yet.  please stick to (ho ho) facts.

ok
dpm
-- 
murphy@npri6.npri.com 602 Cameron St. Alexandria, VA 22314 (703) 683-9090

              When every one is dead the Great Game is finished.  Not before.
                              --- Hurree Babu, "Kim"
From: bweiner@ruhets.rutgers.edu (Benjamin Weiner)
Newsgroups: sci.physics
Subject: Re: waves
Date: 17 Dec 92 00:42:25 GMT
Organization: Rutgers Univ., New Brunswick, N.J.

brian@quake.sylmar.ca.us (Brian K. Yoder) writes:

[claim that light cannot be a wave because you need a thing to wave]

> rickert@cco.caltech.edu (Keith Warren Rickert) writes:
>>The ability to predict experimental behaviour correctly is the real
>>test of a theory, not whether or not it can be visualized.

>I am not claiming that such theories are false because they cannot be 
>visualized.  I am claiming they are false because they are irrational.

Who told you that was grounds to reject a scientific theory?  In any
case I recommend you go and read a book on the history of physics -
look up "luminiferous ether" in the index.

And STOP CROSSPOSTING this gibberish to eight groups!!!  Don't you
people know to edit the "Newsgroups:" line?  In fact you might
consider not posting this gibberish to sci.physics either.
Newsgroups: sci.physics