HDTenEightyP/NetNews huggingface dataset:
From: mcfarlan@corona.math.washington.edu (Thomas J. McFarlane)
Newsgroups: sci.physics
Subject: Re: Report on Philosophies of Physicists
Date: 31 Aug 92 09:31:01 GMT
Article-I.D.: u.1992Aug31.093101.17646
Organization: University of Washington, Mathematics, Seattle

mcirvin@husc8.harvard.edu (Mcirvin) writes:
>QM and relativity are radical ideas, and radically
>at odds with our intuition about the world; and QM, at least, has been
>technologically useful in myriad ways.  But relativity has nothing to
>do with moral or cultural relativism, and QM has nothing to do with
>Taoism or transcendental meditation; just as Darwinism has nothing to
>do with "social Darwinism."
>A little bit of the fault lies with physicists at various times in 
>the 20th century who chose to use terminology and symbolism from 
>Eastern religions, on a whim or in the lack of anything better.  Bohr
>put the Yin-Yang symbol on his coat of arms as a symbol of complementary
>variables

On the contrary, Bohr hardly used the Yin-Yang symbol on a whim.
The principle of complementarity was for Bohr much much more than
just wave-particle duality.  It entered into all our attempts to
understand nature.  He saw the principle of complementarity in other
areas of physics such as relativity, as well as in other areas of
science such as biology.  It had deep philosophical significance for him
and the wave-particle complementarity was just a single instance of
this profound principle, namely, that since no single description
of the world can be a complete description, we need complementary
descriptions to attain a full picture.  He recognized this principle
represented in the Yin-Yang symbol of Taoism.  It was not a whim.

All this is Bohr's *philosophy*, of course, and not physics per se.  But
Bohr *did* see something in common (philosophically) between quantum
mechanics and Taoism, at least in so far as his principle of complementarity
related to both of them in his view.  Anyone who thinks such connections are 
total garbage and has any respect for Niels Bohr might be interested in 
checking out what he actually thought about complementarity.  For example,
Jammer, The Philosophy of Quantum Mechanics
Murdoch, Niels Bohr's Philosophy of Physics

The problem seems to come less from such connections as from the temptation
to either paint such philosophical connections with the certainty of physical
laws or over-generalize the connections based upon one single common principle.
In the first case, there is the tendancy to imply things like "Now Physics has
vindicated the Eastern religions" and in the second case to say things like
"Physics and Taoism are saying the same thing about the world."  Both
physicists and Taoists have a right (and a responsibility) to severely
criticize such irrational conclusions.

Tom McFarlane
From: baez@ucrmath.ucr.edu (john baez)
Newsgroups: sci.physics
Subject: Re: Report on Philosophies of Physicists
Date: 4 Sep 92 19:07:19 GMT
Organization: University of California, Riverside

In article <mcirvin.715559539@husc8> mcirvin@husc8.harvard.edu (Mcirvin) writes:

>Has anybody here worked with quantum logic?  

Yup.

>Does it just include
>an extra truth value to eliminate the excluded middle, 

Nope.

>or is there
>some attempt to turn the mathematics of Hilbert spaces into 
>a system of logic assigning, say, phases and magnitudes to
>various propositions? 

Closer but not quite.  There are various approaches but most of the
better ones work in a roughly similar way.  Propositions in quantum
logic form an orthocomplemented lattice: that is, a set equipped with
operations "and", "or", and "not" satisfying some but not all of the
usual axioms.  The main thing that fails is distributivity of "and" over
"or" and vice versa.  The simplest example of a quantum logic is the
lattice of closed subspaces of a Hilbert space, with intersection as
"and" and closure of the span (=set of all linear combinations) as "or",
and orthogonal complement as "not".  Alternatively we may think in terms
of the orthogonal projections *onto* these subspaces, rather than the
subspaces themselves.   Noncommutativity of the projections gives rise
to the failure of distributivity.  E.g.:

P = the particles is moving to the right (p > 0)
Q = the particle is to the right (q > 0)
R = the particle is to the left (q < 0)

Then 

P & (Q or R) = P

but

(P & Q) or (P & R) = false

"false" being the zero subspace, so distributivity fails.

A state assigns to each proposition an expectation value, that is, a
number between 0 and 1 representing the probability that the proposition
is true.  
 
It's just a nice different way of thinking about quantum theory.  One
can try to see what axioms on the lattice imply that it is the lattice
of subspaces of some Hilbert space, so as to get a "reason" for why
Hilbert spaces are so important in quantum theory.  This project has
been much pursued without definitive success.

There are nice ways to think about superselection sectors and other such
Newsgroups: sci.physics
From: barry@arnold.math.ucla.edu (Barry Merriman)
Subject: Re: Report on Philosophies of Physicists
Organization: UCLA, Mathematics Department
Date: Sun, 30 Aug 92 04:52:47 GMT

In article <1992Aug28.211530.12229@u.washington.edu>  
mcfarlan@corona.math.washington.edu (Thomas J. McFarlane) writes:
> barry@arnold.math.ucla.edu (Barry Merriman) writes:
> >
> >Why not become a _real_ scientist, instead of an intellectual gadfly.
> >(I took plenty of philosophy courses---easy way to fulfil humanities
> >requirements...:-)
> 
> It is sad to see scientists display such a disrespectful and arrogant
> attitude toward philosophy. 

I display and indeed hold such an attitude, and I won't abandon it
until someone shows me what philosophers have contributed to 
our understanding of the physical universe.

(I don't think they've contributed too much to any area
of discourse, but at least in ethics, justice, history, etc its 
hard to tell---their talk is about as good as anyones.
The deficit is  pretty clear in physics, tho.)
--
Barry Merriman
UCLA Dept. of Math
UCLA Inst. for Fusion and Plasma Research
barry@math.ucla.edu (Internet; NeXTMail is welcome)


Newsgroups: sci.physics
From: boswell@fnalp.fnal.gov (Chris Boswell JHU CDF (708)840-3638)
Subject: wanted: info on B meson decay to chi meson
News-Software: VAX/VMS VNEWS 1.4-a4  
Keywords:  B meson decay chi meson ARGUS CLEO
Reply-To: boswell@fnalp.fnal.gov
Organization: Fermilab
Distribution:  world
Date: Sun, 23 Aug 1992 19:54:36 GMT

 Hi, I have a copy of a talk given at the lepton-photon meeting
in Geneva dated July 31 1991 on non-LEP heavy flavor physics,
given my M. Danilov, ITEP, Moscow.  In transparency pages
12 and 13, he mentions the discovery of the decay
B to chi_c X, with an average ARGUS/CLEO branching fraction
of 0.60 %, and the decay B+ to chi_c_1 K+ with average
branching fraction 0.11 %.
 A part of my thesis relies on these numbers, and I was
wondering if there are final results being published bye
ARGUS and CLEO.  Please e-mail me at boswell@fnalp.fnal.gov
or fnalp::boswell if you have decnet. Thank you.

	Chris Boswell
	The Johns Hopkins University
Newsgroups: sci.physics
From: stieger@cco.caltech.edu (Ronald David Stieger)
Subject: Gravity and SR
Keywords: gravity, relativity
Organization: California Institute of Technology, Pasadena
Date: Tue, 1 Sep 1992 21:57:08 GMT

The other day I was thinking (don't ask me why, I try to avoid it as 
much as possible :-) about electric fields and how the field of a moving
charge is not spherically symmetric, and how relativity leads to magnetic
fields.  Then I started wondering whether or not gravitational fields 
behave the same way.  Of course, if I remember correctly, the magnetic
field arises from the fact that there are both positive and negative
charges in a wire, and in different frames of reference these can be at
rest or moving; for gravity, there is only positive mass (unless someone
has made a new discovery recently! :-).  I know very little about 
general relativity, and I suspect it has the answers I'm looking for,
but I don't have the time or energy to look through a bunch of textbooks
for something that may or may not be there and which I may or may not
understand in the context of the book.  And another question I just 
thought of, why is it that mass and gravitational fields curve spacetime?
Why not charge and electric field?  I suspect that it's more than just
a convention, but I don't understand why gravity differs from the other
forces in such a fundamental way.
Anyway, thanks for whatever responses I get.  Hopefully I'll learn something
from them. (Scary thought, huh :-)

-- 
--Ron Stieger
  stieger@cco.caltech.edu
"Hush my darling, be still my darling, the lion's on the phone."
                                               -They Might Be Giants
Newsgroups: sci.physics
From: sneal@muskwa.ucs.ualberta.ca (Steve Neal)
Subject: Re: Prigogine Citation Request
Organization: University Of Alberta, Edmonton Canada
Date: Fri, 4 Sep 1992 08:04:03 GMT

platt@watson.ibm.com (Daniel E. Platt) writes:

>Hi,

>I understand Prigogine published some papers on foundations of
>stat mech where he explored the problem that ergodic systems
>will eventually return arbitrarily close to their initial
>state from the standpoint of quantum mechanics.  If anyone
>happens to know where he actually discussed these issues,
>I'd appreciate citations.

I don't know where Prigogine's work was originally published, but you might 
find the appropriate references in an overview article that was published in
"Science" in the Nov 18, 1977 issue (Vol 198, page 716).  The authors are
Procaccia and Ross.
From: sichase@csa2.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: Radioactive Materials
Date: 1 Sep 92 19:01:11 GMT
Organization: Lawrence Berkeley Laboratory - Berkeley, CA, USA
Distribution: na
Reply-To: sichase@csa2.lbl.gov
NNTP-Posting-Host: 128.3.254.197
News-Software: VAX/VMS VNEWS 1.3-4   

In article <HAGERMAN.92Aug31222916@rx7.ece.cmu.edu>, hagerman@ece.cmu.edu (John Hagerman) writes...

>The long thread on kids eating radioactive stuff started with the fact
>that some lightbulbs have such stuff in them, but that was discussed
>so long ago that I have now forgotten: Why is a radioactive material
>used in the first place?

To ionize the gas in the tube - it helps to start the bulb.

Which reminds me of something Isaac Asimov wrote:  You can tell a physicist
from a layman by how they pronounce this word:

	unionized.

I remember spending about five minutes before I figured out what the
second pronunciation was.

>Actually, what I'd really like to know is: What commercial uses are
>there for radioactive materials, and why those materials?  I'm mostly
>interested in uses that are for reasons *other* than the radioactivity
>aspect of the material.

Half spheres of enriched uranium make wonderful novelty paper weights.

-Scott
--------------------
Scott I. Chase			"The question seems to be of such a character
SICHASE@CSA2.LBL.GOV		that if I should come to life after my death
				and some mathematician were to tell me that it
				had been definitely settled, I think I would
				immediately drop dead again."      - Vandiver
From: bj368@cleveland.Freenet.Edu (Mike E. Romano)
Newsgroups: sci.physics
Subject: Space Poop
Date: 3 Sep 1992 22:58:23 GMT
Organization: Case Western Reserve University, Cleveland, Ohio (USA)
NNTP-Posting-Host: slc5.ins.cwru.edu


This posting was made to the following newsgroups:  sci.environment
sci.astro and sci.physics on Sept 2, 1992.
The posting was deleted from all three newsgroup.
Who does this and why?
Isn't this an unmoderated group?

The following information, again, comes mostly from the journal
Acta Astronautica  July 1992 (I'm grateful no one is removing
the journal from the shelves!):
Since 1957 more than 3,300 launches have produced 7,000 track-
able objects currently in orbit, equalling approx 3000 tons
of man made material.
Of these 7000 objects the US and USSR have produced approx
3300 each.  The rest are from Europe and other countries.

Of these 7000 catalogued objects, only 400 are operational
satellites.  The rest of this number include abandoned or
non functioning satellites, upper stages, and fragments
including lens covers, separation bolts and clamp bands.

Further there are from 30,000 to 70,000 smaller objects but
larger than 1 cm which have not been catalogued.  Any
pieces in this size range can damage spacecraft.

Through the effect of air drag these objects continue to lose
altitude and eventually rain down to earth.
Objects above altitudes of 1000 km are in geo stationary
orbit and will remain there for 1000 years orbitting the
planet 5 million times in this time period and posing a
constant hazard of collision with other objects.

Interactive collisions in earth orbits will eventually
generate sufficient debris to create a dense Debris Belt
and prevent further launchings.
-- 
            Mike Romano     Univ. Calif. Berkeley
From: balbes@ohstpy.mps.ohio-state.edu
Newsgroups: sci.physics
Subject: Re: Axiom of Physics
Date: 27 Aug 92 14:28:34 EDT
Distribution: na

In article <1992Aug27.143522.21625@murdoch.acc.Virginia.EDU>, crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:
> In article <13519.2a9ca679@ohstpy.mps.ohio-state.edu> balbes@ohstpy.mps.ohio-state.edu writes:
>>I'm not sure I would call something that is tested indirectly an 
>>experimental fact.  I would call an experimental fact something that
>>has been measured directly but cannot be calculated exactly, say, like
>>the mass of the proton or electron.  
>>
>>Something that is indirectly tested, such as the constancy (hey, if
>>FDR was allowed to use "normalcy") of the speed of light is experimentally
>>verified only to the limits of our ability to test it.  Just like
>>Newton's laws, relativity might be overturned at any time by one
>>contradicting (and compelling) experiment.  If I think of one I'll 
>>get back to you.
> 
>      In what way is the testing of the mass of an electron or a 
>      proton more 'direct' than the verification of lightspeed?
> 
>      Why do you feel that the same experimental limits that apply
>      to light do not also apply to the properties of electrons?  
> 

Perhaps I stated the above poorly.
I would consider the speed of light to be an experimental fact.  It's
been measured to be c +\- \delta c in some reference frame.  What I would 
consider to be an axiom and not an
experimental fact is that light speed is constant in all reference frames.
Although the equivelence of reference frames is tested indirectly
I don't know of any experiment that says "Light has a constant
speed in all reference frames of c +/_ \delta c where the error
      ^^^^^^^^^^^^^^^^^^^^^^^ 

is the variation in c over all the reference frames."
In my mind (and this is certainly arguing semantics) an experimental
fact is a concrete quantity that has been measured, regardless
of whether or not the quantity can be calculated correctly.
In order to make the measurement you will undoubtably have to invoke some
basic principles (like conservation of energy). I wouldn't consider
an experimental fact a quantity that has been derived using a model.

For example, I can go into a nuclear lab and bombard a target with
a beam and measure cross sections. By looking at the excitation function,
resonance positions can be pinpointed.  I would consider the existence
and positions of these resonances experimental facts because regardless
of any theory or axioms, when I hit these energies my count rate
goes up.  However, if I now
take my data and use resonance theory to find the width of the resonance,
even though I've got error bars for this number I would consider
them to be derived quantities, not experimental fact.

Of course, this is all according to my personal definition of the term 
"experimental fact".  I don't doubt that there are many other
interpretations.  (Oh yeah, and for the budding physicists reading this,
experiments are never as easy or clear cut as my example above.)

Mark Balbes
From: johan@blade.stack.urc.tue.nl (Johan Wevers)
Newsgroups: sci.physics
Subject: Re: E=MC^2
Date: 31 Aug 92 11:58:35 GMT
Organization: MCGV Stack, Eindhoven University of Technology, the Netherlands.

Eric_S_Klien@cup.portal.com writes:

>What is one gram of matter equal to in energy?  In other words, how 
>do you figure out E = MC^2?

If you want the energy from 1 gram of water, just fill in the equation:
E=0.001(3.10^8)^2=9.10^{13} Joule. You can get this amount of energy in
other forms, such as photons, by anihilating the water with anti-mater.
(then 0.5 g water and 0.5 g anti-water are needed for this energy).

******************************************************************** 
* J.C.A. Wevers                *         u\  _\       /e+        2 * 
* johan@blade.stack.urc.tue.nl *     1 |   \ u \  X  /         |   * 
******************************** P = - |    >   >---<     + ...|   * 
*     The only nature of       *     N |   /   /     \         |   * 
*     reality is physics       *         u/   /d     u\            *
********************************************************************
Newsgroups: sci.physics
From: palmer@sfu.ca (Leigh Palmer)
Subject: Re: Why do protons outnumber antiprotons?
Organization: Simon Fraser University
Date: Wed, 2 Sep 1992 22:48:41 GMT

In article <1992Sep1.203413.2683@galois.mit.edu> jbaez@riesz.mit.edu (John C.
Baez) writes:
>In article <1992Sep01.152644.18241@CS.ORST.EDU> cavenej@prism.CS.ORST.EDU
(Jeff Cavener) writes:
>>And for that matter (NPI;-) why do electrons outnumber positrons?
>
>Easy.  If positrons outnumbered electrons we'd call positrons
>"electrons", and if neither outnumbered the other they'd all annihilate
>each other and we wouldn't be around!

John Baez knows that's not strictly correct. In such a short time as the age of
the universe there would surely linger some nonzero particle density, and for
that matter some nonzero neutral matter density. Moreover, the expansion of the
universe does not facilitate recombination as time goes by. No one, to my
knowledge, has been able to convincingly demonstrate what that density would
be, and Alfven believed it would be just that which is presently observed.

I'd like to thank Scott Chase for his straightforward review (which he
acknowledges is not entirely his own) in which he cites several entirely
persuasive arguments for asymmetry on a scale out to galactic cluster size. He
then admits that evidence at larger scales is less robust. I will point out
that the persuasive arguments, strong as they may be, should be given no weight
whatsoever in deciding the issue. Recall that Aristotle "knew" that the Earth
is spherical. After all, the shadow of the Earth seen on the moon at time of
lunar eclipse is circular. To strengthen his argument he added that, since
there are elephants in India and also in Morocco, India and Morocco must be
close together!

I consider the question of baryon asymmetry to be an unanswered question in
science, and perhaps one of the very most important. *The* most important
question, of course, is simply this: 

How much of that which is common knowledge is also false?

Here again I believe the answer to be nonzero.

Leigh
Xref: sparky sci.physics:13680 sci.skeptic:15143 alt.folklore.science:3173
From: klaus@diku.dk (Klaus Ole Kristiansen)
Newsgroups: sci.physics,sci.skeptic,alt.folklore.science
Subject: Re: The dangers in microwaved food...
Date: 25 Aug 92 11:09:25 GMT
Organization: Department of Computer Science, U of Copenhagen

david@euclid.JPL.NASA.GOV (David Bernath) writes:


>>>In article <1992Aug20.015531.7842@nuscc.nus.sg> matmcinn@nuscc.nus.sg (Mcinnes B T (Dr)) writes:
>>>there are serious health risks in eating.
>>
>>There are serious health risks.

>Health is a serious risk.

Be serious.
From: sichase@csa1.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: Report on Philosophies of Physicists
Date: 30 Aug 92 20:09:48 GMT
Organization: Lawrence Berkeley Laboratory - Berkeley, CA, USA
Distribution: na
Reply-To: sichase@csa1.lbl.gov
NNTP-Posting-Host: 128.3.254.196
News-Software: VAX/VMS VNEWS 1.3-4   

In article <mcirvin.715196487@husc8>, mcirvin@husc8.harvard.edu (Mcirvin) writes...
> 
> ... relativity has nothing to do with moral or cultural relativism, and QM 
> has nothing to do with Taoism or transcendental meditation; just as 
> Darwinism has nothing to do with "social Darwinism."

We need to print this statement on our money, or add it to the national 
anthem or something.  If I had a dollar for every time I had a conversation
with someone who didn't understand this, I could fund the SSC by myself.

-Scott

--------------------
Scott I. Chase			"The question seems to be of such a character
SICHASE@CSA2.LBL.GOV		that if I should come to life after my death
				and some mathematician were to tell me that it
				had been definitely settled, I think I would
				immediately drop dead again."      - Vandiver
From: crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass)
Newsgroups: sci.physics
Subject: Re: Axiom of Physics
Date: 26 Aug 92 19:36:09 GMT
Distribution: na
Organization: University of Virginia

In article <25781@dog.ee.lbl.gov> sichase@csa3.lbl.gov writes:
>In article <1992Aug26.174922.6115@pellns.alleg.edu>, frisinv@alleg.edu writes...
>>A friend and I have a small disagreement about the existance of an axiom  
>>of physics. She claims that all assumptions in physics are made from  
>>empirical evidence and therefore there are no axioms in physics. I  
>>maintain that the conservation of mass/energy is an axiom. Here is my  
>>argument: an axiom must be based on evidence. Euclid didn't just say  
>>parallel lines don't intersect, he saw evidence that they didn't and then  
>>stated the postulate. We have seen that energy and mass seem to be  
>>conserved. There is very strong evidence that they are conserved but (to  
>>my limited knowlege) there is no proof that they are conserved in all  
>>cases. Thererfore, conservation of mass/energy is an axiom of physics. Can  
>>anyone think of other axioms of physics?
>
>Sometimes axioms are used in physics.  Special relativity might be a good
>example.  There was evidence that things did not work as expected according
>to Newton.  Einstein came along with a new axiom - the speed of light is
>the same in all inertial frames of reference - and found that the theory 
>which can be derived from this axiom explained some otherwise bizzare 
>experiments, and made some verifiable predictions as well (which turned
>out to be correct, of course.)  
>
>Whether we would still say, almost 90 years later, that "the speed of light
>is the same in all inertial frames" is still an axiom or an experimental 
>fact is a different matter.  
>
>Eventually, one hopes that all axioms undergo direct experimental test,
>verifying the fundmental assumptions of the theory by direct confrontation
>with reality.  At that point, I suppose they loose their status as axioms
>and become experimental facts.

    I am not sure that the differentiation between an 'axiom' and
    an 'experimental fact' (say the fact that we have never seen anything
    have true speed greater than c for example) is very fruitful.  After all, 
    in our example, the speed of light limit can still be considered
    to be an axiom of our physical system in that it is an assumption with
    only an experimental basis.  The amount of experimental verification
    does not seem to alter its status as an axiom.

    By the way, I suspect that a physical theory with no axioms does not
    and even cannot exist.

                                 dale bass

-- 
C. R. Bass                                           crb7q@virginia.edu
Department of Mechanical and Aerospace Engineering
University of Virginia
Charlottesville, Virginia                            (804) 924-7926
Newsgroups: sci.physics