HDTenEightyP/NetNews huggingface dataset:
From: baez@guitar.ucr.edu (john baez)
Newsgroups: sci.physics
Subject: Re: John Baez's remarks on parallel slit kets vs. perpendicular slit kets in standard quantum optics.
Date: 24 Nov 92 00:48:59 GMT
Organization: University of California, Riverside

In article <By5Ewn.BFF@well.sf.ca.us> sarfatti@well.sf.ca.us (Jack Sarfatti) writes:
>
>Well John Baez you don't like "super"? How about superposition?
>superstring? superfluid? superconductivity? superstition? supercilious?

I went through the whole list already a while ago.  I don't like "super" as
an intensifier when there is no objective reason for using it.  

>Are you saying that Princeton University supports crackpot science in their
>PEAR laboratory headed by Dean of Engineering, Robert Jahn with money from
>Mc Donnell Douglas and Federal Intelligence Community?

The issue is hotly debated, e.g. in recent issues of Physics Today.  But
I didn't say it was "crackpot."  I just said that assuming it's right is
a case of a "big if".

>But what about the substantive issue. Parallel slit kets seem to work as
>well as perpendicular ones. If not, why not?

>Linearity seems to contradict local dynamics. 

Since I have not been following your debate with Ramsay closely, I can't
easily follow the notation in the rest of your post, but I will simply
say that linearity does not contradict local dynamics.  Let me just note that
the paradigm of linearity combined with local dynamics is as follows.
If a system consists of 2 remote subsystems we describe it's Hilbert space
as the tensor product H_1 x H_2 of the Hilbert spaces for the two subsystems,
and we say a unitary operator (typically that implementing time evolution) is
"local" if it is of the form U_1 x U_2 with U_i a unitary operator on H_i.
Standard QM says that if the systems are far enough away and the interaction
takes place in a short enough time so that light can't get from one subsystem 
to the other, the unitary time evolution on the whole system *must* be local
in this sense.


Xref: sparky sci.physics:19394 talk.bizarre:39021
From: lnh@soliton.physics.arizona.edu (sometimes a Wombat)
Newsgroups: sci.physics,talk.bizarre
Subject: Re: Short Shamefull Physics
Date: 19 Nov 92 20:32:22 GMT
Organization: Society for the Appreciation of Janni Lee Simner

jcarroll@ferris.cray.com (Jeff Carroll) writes:
> 
> There are practical difficulties associated with building a WG
> in the shape of a Klein bottle.

It's not MY fault your department won't (or can't) shell out for a
decent hyperspace tank.

(Hint:  If you get one, don't tell the astro people -- they'll want to
monopolize it for stellar evolution experiments.)

	Larry "Now we need two" 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
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Re: Lowneheim-Skolem theorem (was: Continuos vs. discrete models)
Organization: MIT Department of Mathematics, Cambridge, MA
Date: Sun, 22 Nov 92 23:06:33 GMT

In article <1992Nov22.002703.5865@CSD-NewsHost.Stanford.EDU> pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt) writes:
>In article <368@mtnmath.UUCP> paul@mtnmath.UUCP (Paul Budnik) writes:

>>The discussion on L-S has apparently misled you. I believe that the
>>space-time manifold is discrete, i. e. not continuous. There are many
>>ways to discriminate between a continuous and discrete model and this
>>has nothing to do with countability.
>
>So why this raging debate about how many reals, then?

Typically, issues which have no practical significance generate more
raging debates on sci.physics than those which do.
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Re: No Spin in 2 Dimensions?
Organization: MIT Department of Mathematics, Cambridge, MA
Date: Tue, 17 Nov 92 23:19:55 GMT

In article <FRANL.92Nov16233347@draco.centerline.com> franl@centerline.com (Fran Litterio) writes:
>hoconnel@iti.org (Heath O'Connell) writes:
>
>> zowie@daedalus.stanford.edu (Craig "Powderkeg" DeForest) writes:
>> 
>> > but then QM doesn't work too well with SR anyway
>> 
>> QM and SR work quite well together.
>
>Then how do you reconcile wavefunction collapse with the relativity of
>simultaneity?

You don't; you recognize wavefunction collapse for the myth it is.  We
have, of course, been through this before, and not everyone agrees with
my solution.  (Just everyone who is right.  :-))

The real problem is that nobody has come up with a provably consistent
theory of interacting particles in four dimensional spacetime that
satisfies the principles of both special relativity and quantum
mechanics.  It's for this reason that I'd say "QM and SR work quite well
together" is misleading.  Again, this is something I frequently point
out.
Newsgroups: sci.physics,sci.math
From: daryl@oracorp.com (Daryl McCullough)
Subject: Re: Three-sided coin
Organization: ORA Corporation
Date: Mon, 23 Nov 1992 14:53:51 GMT

In article <1ei041INNec2@chnews.intel.com>, bhoughto@sedona.intel.com
(Blair P. Houghton) writes:

>In article <1992Nov17.130147.26746@oracorp.com> daryl@oracorp.com (Daryl
>McCullough) writes:
>>bhoughto@sedona.intel.com (Blair P. Houghton) writes:
>>>Summary: probability is distributed according to entropy, not energy
>>
>>If we are talking about a flipped coin, I don't think it is
>>distributed according to either. The probability distribution on coins
>>depends on the way the coin is flipped and the initial orientation.
>>For example, if my coin is a cylinder (three sides), and flipping
>>consists of rolling it, then it has essentially zero probability of
>>landing on either of its two ends.
>
>Don't do that.
>
>You are further constraining the system, and thus
>altering its entropy at the outset.

I'm not *further* constraining the system. Coin-flipping is a physical
process, not a mathematical one, and there is no reason a-priori to
believe that your entropic analysis will give you anything vaguely
resembling the observed frequency.

As a matter of fact, do you know of *any* way to flip a coin such that
the observed frequencies will correspond to your entropy calculation?
I certainly don't. So what is the value of your calculation? What is
the meaning of the result?

>You are correct that, given the new initial conditions, the
>probability is almost unity that the coin will remain
>"on-edge."  This is because you have made the change of
>state from on-edge to on-face an entropy *decreasing*
>event.

What do you mean, *new* initial conditions? What were the original
initial conditions?

>You can't constrain the system with anything other than
>"what is the probability that the coin will end up on its
>edge?"  Even if you say the coin is flipped, you have
>constrained the form of motion and therefore altered the
>entropy.

I don't understand what you could possibly mean by "the probability
will end up on its edge" independent of a mechanism for flipping the
coin.

>In order for the entropic analysis to work, the method of
>reorienting the coin, and indeed whether the coin is
>reoriented or left alone, must remain unknown, and be
>allowed to assume all possible values; otherwise, you end
>up with a morass of conditions and trajectories and phase
>spaces and the need to define *everything* [*] rather than
>*nothing*.

I don't understand what you mean by the entropic method "working".
The question is, does it give the correct relative frequencies?  I
don't see any reason why it should. And if your probability
calculation is not an attempt to predict relative frequencies, then
what is it for?

Daryl McCullough
ORA Corp.
Ithaca, NY
Newsgroups: sci.physics
From: geg@beep.mis.semi.harris.com (Gregory E. Garland)
Subject: Re: Inelastic versus Elastic
Date: Mon, 23 Nov 1992 21:09:38 GMT
Organization: Manufacturing Systems, HSS

In article <1992Nov22.101430.455@news.wesleyan.edu>, BBLAIS@eagle.wesleyof r
(BRIAN S. BLAIS) writes:
|> A friend of mine wrote me:
|> --
|> Suppose that you have a bullet running into a block. It does so in a
|> perfectly
|> inelastic manner. That is, the bullet stays in the block after the collis
|> imparting its momentum into the combination of itself and the block.
|> However,
|> some of the energy of the motion is lost in the form of heat, so kinetic
|> energy is not conserved.
|> 
|> Why? I am looking for an intuitive explanation of the conservation of mom
|> that allows one to see clearly and distinctly that, even though some of t
|> quantity of motion is converted into heat, the quantity of motion as
|> expressed
|> by _mv_ remains the same.
|> --
|> 
|> 	I was trying to think of some reply to this, and thought that people
|> one the Net might like thinking about it.  I would like to know if anyone
|> has
|> any good way of looking at this problem.
|> 
|> 			Brian Blais
|> 

Since there is no external force on the system (and if you assume all
the
internal forces involved in the bullet/block collision are "nice" enough),
then you expect the momentum to be conserved.  To see why the kinetic energy
is not and to see where the energy that deforms and heats up the materials
comes from, look at the kinetic energy in terms of the motion of the
center of mass of the bullet/block system.  The c. of m. plods along at
constant velocity before and after the collision, and gives the same 
contribution to the energy before and after. The motion of the bullet
and block relative to the c. of m. before the collision has some non-zero
contribution to the kinetic energy, but after the collision is zero.

-- 
Greg Garland - Alive, occupying space, and exerting gravitational force

MS 62-024, Harris Semiconductor Sector, PO Bx 883, 
Melbourne  FL 32905.  geg@beep.mis.semi.harris.com

"Never let the facts interfere with your perception of reality."
From: sichase@csa3.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: Calculation of G
Followup-To: sci.physics
Date: 23 Nov 1992 12:24 PST
Organization: Lawrence Berkeley Laboratory - Berkeley, CA, USA
Distribution: world
NNTP-Posting-Host: 128.3.254.198
Keywords: Reciprocal System, Derivation of gravitational constant
News-Software: VAX/VMS VNEWS 1.41    

In article <1992Nov22.213716.19071@isus.UUCP>, hoyt@isus.UUCP (Hoyt A. Stearns jr.) writes...
>In article <9NOV199212382504@csa2.lbl.gov> sichase@csa2.lbl.gov (SCOTT I CHASE) writes:
>>>G can be calculated from basic Reciprocal System principles to
>>> the minimum accuracy of the three numbers used as a starting point:
>>>	c, Avogadro's number, and the Rydberg frequency.
>>> 
>>Would you please demonstrate a derivation of G from this data?
>>
>Here is a derivation:

[...Derivation omitted...]

This was interesting, but you have not presented it in a way that I 
could follow completely.  I'll try to extract the essentials.  You
say that:

>So G<cgs> = 3N/Mc^3 = 6.66559478 E-8 dyne-cm^2/g^2

So naturally, I looked back in your proof to find the values of M and N.  
I found:

>Define M the mass in amu of a natural unit of mass.
>M = 1 + 1/(128*(1+2/9)) = 1.00639205 amu.

So far so good.  But when I tried to find out how N is defined, all
I got was:

>1 mole of natural mass units = M  grams<cgs>
>#	M/N (unit-mass<gram>/unit-mass<nu>).

What does this mean?  

-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: doug@retzlaff.llnl.gov (Douglas S. Miller)
Newsgroups: sci.physics
Subject: Re: Volume of Cyl. Shell and Thermodynamics
Date: 18 Nov 92 22:31:55 GMT
Organization: UC Davis Dept of Applied Science at LLNL

mustafa@seas.smu.edu (Mustafa Kocaturk) writes:
>doug@wente.llnl.gov (Douglas S. Miller) 
>[calculates the approximate weight of a hollow cylindrical tank:]
>>           ...  The weight of the tank, however, will go roughly as wall 
>>thickness squared (mass = density*pi*(r_outer^2-r_inner^2)*height), so now 

[M.K. doesn't agree with r^2 conclusion]

>
>   Proof:
>   Using elementary algebra to write (ignoring the bases of the cylinder)
>       r_outer^2 - r_inner^2 == (r_outer + r_inner)*(r_outer - r_inner)
>   and assuming r_outer+r_inner is kept constant (by keeping the average
>   diameter constant), it follows that the weight of the tank
>   is *proportional* to its thickness.

Keeping the average constant means decreasing r_inner as r_outer 
increases.  This works until r_inner -> zero, at which point the tank 
holds nothing, which is not very useful (paper weight for hurricane
country?).

>
>   Secondly, other things may happen before thickness grows
>   out of control. The gas inside the tank will probably change state
>   (liquefy or solidify) under that pressure, if some of its

If the compressed gas changes phase at room temperature and 100,000 psi
then this idea is *really* in trouble; remember the original thought
was to use compressed air to run cars.  Anybody got a phase diagram
for nitrogen?  I've no idea how warm it can get and still go to liquid at 
high pressure.  Btw, Blair Houghton noted that I dropped a factor of 
10 on the weight of the tank, it's ~32,000 pounds, not 3200.  Pretty
hefty load for, oh let's say a Chevette.

Doug Miller	doug@retzlaff.llnl.gov
"St. Peter, don'cha call me, 'cause I can't go.
 I owe my soul to the Company Sto'."
Newsgroups: sci.physics
From: palmer@sfu.ca (Leigh Palmer)
Subject: Re: 3-sided coin
Organization: Simon Fraser University
Date: Tue, 17 Nov 1992 20:26:23 GMT

In article <1e98b8INN6s@manuel.anu.edu.au> butler@rschp2.anu.edu.au (Brent
Butler) writes:
>The solution to this problem is simple.  When a coin is flipped it
>will *come to rest* in a position that represents a minimum in its
>(gravitational) potential energy.  For a real coin this means one
>of its two faces with equal probability - it will never *come to
>rest* on its edge even though it has a finite area because this is
>a metastable state.

It is a stable state. A finite displacement from equilibrium (or a most
unlikely quantum process) is required for it to topple; that is a stable state.
If it is not, then either "heads" or "tails", whichever has the lower energy,
is also a metastable state.

I have a colleague, Dan Murray, who did experimental and theoretical work on
the problem of coins landing on edge while a graduate student at Guelph
University in Ontario. He has a videotape showing a coin landing on edge.

Leigh
From: ande@sierra.com (Ande Rychter)
Newsgroups: sci.physics
Subject: Scientists debunk astrology...and what else?
Date: 16 Nov 92 19:06:51 GMT
Organization: Sierra Geophysics Inc.,  Kirkland, Wa

In <1992Nov11.024228.19183@nuscc.nus.sg> Brett McInnes writes:

> I have tried [without much success] to follow the thread on mixing
> science and religion. I note that many people argue that the two are
> indeed immiscible. I wonder how these people feel about astrology? Many
> of us feel that scientists have a moral obligation to speak out against
> popular delusions of this kind. Are we mistaken? Should we take the view
> that astronomy and astrology don't mix?


Astrology is to astronomy what MacDonald's food is to gourmet dining.  
Should we speak out against it?  For as long as the people who believe in 
astrology are eligible to vote - absolutely! -AR.
Newsgroups: sci.physics
From: gustin@evs2.uia.ac.be (Emmanuel Gustin)
Subject: Re: Religion & Physics Don't Mix
Organization: U.I.A.
Date: Mon, 16 Nov 1992 02:59:34 GMT

Okay, science can't tell us anything about religion; a God you can subject
to scientific study is not a God but a part of nature. The other way
around is possible; because if God knows everything, He could tell us
something we don't know, and if he is all-powerfull, the He can show his
powers, doing the impossible. And most religions tell us He did...
However, then we COULD make a scientific study about His existence,
implying that God is part of nature, and thus cannot act against nature's
laws. So all this logic adds up to nothing. My hasty conclusion: whether
you believe God exists or not, logic won't help you to convince anyone.

More important: Science can't accept religion as a part of its structure -
nor superstition of prejudice.  But religion has to accept logic and
science, and many religious people have no trouble with that - what the
pope tried to show when he apologized for the Galilei trial. Theology is
based on faith but is not a purely mystical affair. As G.K. Chesterton
made father Brown say when caught fake priest: attacking Logic is bad
theology. People can't (at least not forever) believe in something that is
clearly not true. Thus mixing religion into science is *impossible*, but
mixing science into religion is an *inevitability*. 

Yes, I know there are lots of people who refuse to mix some science in
their religion - creationists and others. But don't blame religion for
this; it's bad science AND bad theology. It is true that religion is
conservative by nature and evolves slower than science, because religious
people find it hard to admit that their beliefs are not THE thruth - maybe
because they are more important to them than Schrodingers equation to a
scientist, even an 'elderly' scientist.

E. Gustin 


Xref: sparky sci.physics:19089 sci.astro:12110
From: bhoughto@sedona.intel.com (Blair P. Houghton)
Newsgroups: sci.physics,sci.astro
Subject: Re: Higgs Spotted? (really about Mars)
Date: 17 Nov 1992 20:14:13 GMT
Organization: Intel Corp., Chandler, Arizona
NNTP-Posting-Host: alfalfa.intel.com

In article <1992Nov16.231844.28715@murdoch.acc.Virginia.EDU> crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:
>      Are you saying that the likelyhood of there being water on Mars
>      is the same as the likelyhood of the moon being made of cheese?
>      I'd have to say that this is wildly at variance with current theory.

I'm saying that the likelyhood of Dan Quayle's being a
deserving and competent holder of the second-highest
executive office in the United States Government is
lower than the probability that you will renounce God
and kiss me on the Mystery Leptons.

Dan Quayle's faith in a wet Mars is on par with your faith
in a benevolent diety; it's mythical, and not deserving of
a slot on the "Why We Fly A Man To Mars" decisionmaking
checklist.

I bet Dan thinks Ben Franklin discovered electricity.

				--Blair
				  "Yeah.  What he said."
From: cain@geomag.gly.fsu.edu (Joe Cain)
Subject: Re: Higgs Spotted? (really about Mars)
Followup-To: talk.politics.space
Organization: Florida State University Geology Dept.
Date: Wed, 18 Nov 92 13:13:07 GMT

Hey people, Quayle is passe so please let this thread go. If you must
continue, take it to talk.politics.space. If you want to discuss Mars,
ok, but reasonable questions.

I gave his quote to 74 students in an introductory planetary geology
class (for poets) and only one did not understand the situation. Of
course now I have to explain that water does not create lasting
oxygen on a planet.
Joseph Cain		cain@geomag.gly.fsu.edu
cain@fsu.bitnet		scri::cain
Newsgroups: sci.physics
From: crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass)
Subject: Re: Religion & Physics Don't Mix
Organization: University of Virginia
Date: Mon, 16 Nov 1992 16:40:08 GMT

In article <1992Nov16.142049.203282@uctvax.uct.ac.za> wnljam01@uctvax.uct.ac.za writes:
>
>--)) You are a religious scientist!  Your religion is clearly humanism - this
>makes man's reasoning autonomous and the ultimate reality.  Humanism states
>that there are no god's but those which man invents in his own mind.  In other
>words humanists exalt man as god.  
>It is very interesting to see how often scientists refer to the wonderful
>workings of 'Nature' (capital n!!) in the literature.  So many scientists
>refuse to ascribe the observed incredible order and symmetry of nature to an
>intelligent Creator God.  I think this is plain stupid and the Bible calls
>people who are blind to the genius in creation fools.  Ditto.

     Whether it is 'stupid' or not is certainly not the business of
     science.  And scientists should certainly refuse to ascribe behavior
     of the sort you mention to an 'intelligent Creator God' within 
     science.  What they do at other times is none of *my* business.

                                     dale bass


-- 
C. R. Bass                                          crb7q@virginia.edu        
Department of Mechanical, 
     Aerospace and Nuclear Engineering
University of Virginia                              (804) 924-7926
Newsgroups: sci.physics
From: crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass)
Subject: Re: Why is "Physics Today" so expensive?  (Are there student discounts?)
Organization: University of Virginia
Date: Tue, 17 Nov 1992 00:53:34 GMT

In article <41095@sdcc12.ucsd.edu> ph600fcy@sdcc14.ucsd.edu (Matthew Harrington) writes:
>I looked into subscribing to Physics Today and I was
>shocked that the price was something like $125 for a monthly.  I get
>Science for $47 and it is a weekly!
>
>I know that I should write P.T. with this question, but I'm
>impatient and don't want to wait a month for the reply.  So, is
>there a less expensive way for undergraduates to get Physics Today,
>or am I stuck with trying to find it at the library, where it is
>frequently in use?  Thanks in advance,

     Look into becoming a member of the American Physical Society.
     For $20 a year as a student member, you get Physics Today free.
      
>PS. Also, are there other general physics periodicals which net.people
>recommend?  Nothing too technical -- just the facts, ma'am.

     Nature, Science, New York Times on Tuesday.  These are not restricted
     to just physics.

     On a lower level, there are those who like New Scientist.  I am afraid
     that it is an acquired taste that I never acquired.
     Scientific American has been running hot and cold (mostly cold) 
     recently.  There's always Popular Science for the neeto gadgets that
     show up there.

     In the end, it is often difficult to 'get the facts' without getting
     technical.

                               dale bass


-- 
C. R. Bass                                          crb7q@virginia.edu        
Department of Mechanical, 
     Aerospace and Nuclear Engineering
University of Virginia                              (804) 924-7926
From: columbus@strident.think.com (Michael Weiss)
Newsgroups: sci.physics
Subject: Re: Lowenheim-Skolem theorem (was: Continuos vs. discrete models)
Date: 19 Nov 92 15:14:02
Organization: Thinking Machines Corporation, Cambridge MA, USA
	<TORKEL.92Nov18193457@bast.sics.se>
	<COLUMBUS.92Nov19105153@strident.think.com>
	<1992Nov19.172844.17787@ulrik.uio.no>
NNTP-Posting-Host: strident.think.com
In-reply-to: rivero's message of Thu, 19 Nov 1992 17:28:44 GMT

In article <1992Nov19.172844.17787@ulrik.uio.no> rivero
<rivero@cc.unizar.es> writes: 

   Wasnt L-H theorem the kind of things that let you go in both directions?
   This is, given a model, you can get ones with lower cardinality, and
   others with higher. 
   I think to remember that you can always go higher by using 
   Los theorem, ultraproducts, or something so?. This was the thing
   Robinson did to go over no-standard (*), is this? 

Quite true: the simplest "upward" L-S theorem asserts that if a theory with
a countable language has an infinite model, then it has models of arbitrary
cardinality kappa.  This is easy to see from the completeness theorem: just
add kappa constants to the language, and axioms stating that they are all
distinct; you can easily show from the hypothesis that this extended theory
is consistent, so it has a model.
Newsgroups: sci.physics