HDTenEightyP/NetNews huggingface dataset:
From: music@reg.triumf.ca (FRED W. BACH)
Newsgroups: sci.physics
Subject: Re: Calendar (NEW)
Date: 28 Aug 92 18:47:00 GMT
Organization: TRIUMF: Tri-University Meson Facility
News-Software: VAX/VMS VNEWS 1.41

In article <2905@ucl-cs.uucp>, P.Samet@cs.ucl.ac.uk (Paul Samet) writes...
>Actually Easter is the first Sunday following the first full moon which occurs
>on or after March 21 (Spring equinox), not March 20, as claimed.
> 
>See D. E. Knuth, Art of Computer Programming, Volume 1, exercise in sect 1.3.2,
>for a way to calculatethe date of Easter, after 1582, showing some of the traps
>that can occur if it's done wrong, Knuth invites the reader to implement a 16th
>century algorithm.
> 
>He also suggests that calculating the date of Easter was the sole important of
>arithmetic in Europe during the Middle Ages.
> 
>Paul Samet

   As a bit of an aside, the proper way to calculate the date of the
 passover from what I have learned should be this (although there may
 be a variance of 1 day in modern times) :

     After sundown, two weeks after the NEW MOON (as seen from Jerusalem)
     closest to the spring equinox.

     The month of NISAN started with the new moon closest to the spring
     equinox.  Sometimes it would be BEFORE the spring equinox, and
     sometimes it would be AFTER.  (These were LUNAR months).  The passover
     was on the 14th day of NISAN, and the days started in the evening.

  Does anyone have any authentic corrections to this?

 Fred W. Bach ,    Operations Group        |  Internet: music@erich.triumf.ca
 TRIUMF (TRI-University Meson Facility)    |  Voice:  604-222-1047 loc 278/419
 4004 WESBROOK MALL, UBC CAMPUS            |  FAX:    604-222-1074
 University of British Columbia, Vancouver, B.C., CANADA   V6T 2A3

 These are my opinions, which should ONLY make you read, think, and question.
 They do NOT necessarily reflect the views of my employer or fellow workers.
From: sichase@csa1.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: Why do protons outnumber antiprotons?
Date: 4 Sep 92 19:07:59 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 <4SEP199211025027@zeus.tamu.edu>, dwr2560@zeus.tamu.edu (RING, DAVID WAYNE) writes...
> 
>The point is an electron and a neutrino are just components of one
>particle. Consider instead the process N + nu -> P + e- . The lepton
>particle is still there above the sea, it has just rotated into a different
>component. In your process a lepton was pulled out of its sea and at the same
>time rotated. I claim in fact that there is nothing inconsistent about
>the hole interpretation for fermions (until you get to supersymmetry).
>I don't really know this but I've argued with my advisor about it without
>any real conclusion.

But the electron and the antineutrino are not identical with one another.
So it seems to me that you need two separate Dirac seas, each supported 
by its own Fermi pressure, so to speak.  Even if you think of an electron as a
rotated neutrino, then after the process you describe above, without a 
separate electron sea the final state electron will end up in a negative
energy state.  

-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: finn@isi.edu (Greg Finn)
Newsgroups: sci.physics
Subject: Re: Report on Philosophies of Physicists
Date: 31 Aug 92 17:07:13 GMT
Reply-To: finn@dalek.isi.edu (Greg Finn)
Organization: USC-Information Sciences Institute

In article <1992Aug30.045247.19483@math.ucla.edu> barry@arnold.math.ucla.edu (Barry Merriman) writes:

>> 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.)

	You are provincial if you are unaware of the influence
	of philosophers on early science and mathematics.  What we now
	call science was once a specialization of philosophy.
--
Gregory Finn	(310) 822-1511
Information Sciences Institute, Marina Del Rey, CA 90292
From: sichase@csa2.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: Facts and Values
Date: 24 Aug 92 02:29:08 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 <QeZvN_O00VAwQ0q5AU@andrew.cmu.edu>, ag3l+@andrew.cmu.edu (Arun K. Gupta) writes...
> 
>Scott, the very fact that physics has not shown any need for soul,
>afterlife, heaven and so on, and the tremendous success of science
>have given cause for people to doubt the religions they once took
>for granted.

The Frugal Gourmet has not shown any need for soul, afterlife, or heaven - 
but people haven't abandoned religion because of him.    You logic is 
badly flawed.  Physicists are no more capable of addressing these issues
than Jeff Smith is.  

It is true that old religious texts contain factually inaccurate material.
Only those people who foolishly cling to the literal inerrancy of 
reigious texts have a problem with the obvious fact that theese books,
though written by spiritually enlightened people, were also written by
people who could not have known twentieth century physics and biology.

>One indication of how much the religious leadership envies and fears
>this success is in the movements that purport to show that the Qu'ran
>contains scientific predictions and that a grand unified field theory
>can be found in the Hindu Vedas, and so on.

Now we've come back to the statement I started out this tread with - 
only foolish fundamentalists with little or no understanding of either
science or theology insist upon trying to use religion to address the 
properties of the material world, or physics to answer moral questions.

>The intellectual respectability of religion as a way to look at
>the universe is eroding rapidly, and this shows up in our value
>systems.

Just because physics does not address moral issues does not mean than religion
is the old means of doing so.  I personally have well-defined morals by
which I choose to live - but no God to force them upon me - and no God
but myself to punish or forgive me if I err.

-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
Newsgroups: sci.physics
From: jbaez@riesz.mit.edu (John C. Baez)
Subject: Re: Length scales in physics 4 - the Planck length
Organization: MIT Department of Mathematics, Cambridge, MA
Date: Mon, 31 Aug 92 22:02:34 GMT

In article <1992Aug27.042512.23227@nuscc.nus.sg> matmcinn@nuscc.nus.sg
(Mcinnes B T (Dr)) writes: 
>dwr2560@zeus.tamu.edu (RING, DAVID WAYNE) writes:
(Mcinnes writes:)
>: >errr....meaning what? how do you "treat spacetime as a field?"
>: 
>: You can do the same thing with a point particle. It's path is given by
>: R(t) where R is a four-vector, and t is the particle's proper time, or any
>: other parameter. You can consider the particle to live in R space, or you
>: can consider R to be a field living on the one dimentional t line. Then you
>: can do a path integral over all paths R(t) or a functional integral over
>: all fields R(t).
>: 
>All right, I guess you can call this "treating spacetime as a field".
>But then it would seem that string theory indicates that nothing weird
>happens to spacetime at small lengths: you always have a well-defined
>target space.

Yes, exactly.  As recently discussed, this is related to a big esthetic
drawback of existing formulations of string theory.  Namely, the strings
propagate on a spacetime with a fixed "background" metric.  String
theory is supposed to be a quantum theory of gravity and in general
relativity the metric is a dynamical variable.  That is, there is no unique
God-given "background" metric on which gravitational ripples roam; there
are just lots of solutions of Einstein's equations.  The philosophical
problem with trying to perturbative quantization of GR is precisely that
one is according flat spacetime a privileged role and treating other
solutions as ripples on this background, aka "gravitons".   So, as
someone who likes string theory more than I do admitted in a recent
post, it would be much nicer if one could do string theory without using
a background metric.  Admittedly, this is a philosophical/esthetic
problem rather than an inconsistency.   But our poster admitted that a
background-free version of string theory was the "holy grail", and noted
that Witten's latest paper is an attempt in this direction.

The loop variables formulation of quantum gravity, on the other hand, is
manifestly nonperturbative and uses no background metric.  (It has other
problems, true - mainly, that not enough work has been done on it yet!)
From: sichase@csa1.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: Axiom of Physics
Date: 30 Aug 92 20:13:10 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.715198792@husc8>, mcirvin@husc8.harvard.edu (Mcirvin) writes...

>of the evidence.  For now we have to rely on things like the parton
>model, the infinite-mass approximation for heavy quarks, and other stuff
>that is not strictly included in the axioms.  Lattice gauge theory is
>closer to doing calculations with QCD directly; it's in its infancy, and
>the extent to which it succeeds will depend in part on the availability
>of sufficiently capable computers. 

I'm always amused when I read a lattice QCD paper which tries to calculate
hadron masses.  The authors always miss the proton mass by more than they
wish they had.  And they always get a proton-pion mass ratio of roughly
3/2.   They spend hundreds of thousands of dollars on parallel computers,
technicians, etc.  Then they spend years of CPU time only to rediscover
that a proton has 3 valence quarks and a pion has only 2.

This is the best we can do?  It's frustrating.

-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
Newsgroups: sci.physics
From: zukicn@wl.aecl.ca
Subject: REACTOR PHYSICIST Position - R&D
Organization: AECL RESEARCH
Date: Thu, 27 Aug 1992 15:18:55 GMT

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Resources and the person listed below. Our phone is: (204) 753-2311. 

Thank you,

Nermin Zukic

----------------------------------------------------------------------------

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        include fuel characterization studies, radiation transport
        calculations, fuel geometry optimization, and reactor operation
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        development to expand existing capability, automate routine
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        An advanced degree in Physics or Nuclear Engineering and a
        strong background in computer programming and utilization are
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        considered.

        While previous experience with neutron diffusion theory,
        multigroup neutron transport theory or Monte Carlo calculational
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                 AECL Research
                 Whiteshell Laboratories
                 Pinawa, Manitoba
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Newsgroups: sci.physics
From: prim!dave@germany.eu.net (Dave Griffiths)
Subject: Information Theory and Quantum Mechanics
Organization: Primitive Software Ltd.
Date: Wed, 26 Aug 1992 17:18:04 GMT


According to July's Scientific American, some theorists are trying to apply
information theory to QM, where "the basis of reality may be... the answer
to a yes-or-no question".

Can anyone enlarge upon this, or point me at any recent papers/books on
this subject?

Thanks,

Dave Griffiths
From: matmcinn@nuscc.nus.sg (Mcinnes B T (Dr))
Newsgroups: sci.physics
Subject: Re: Length scales in physics 4 - the Planck length
Date: 2 Sep 92 03:55:52 GMT
Organization: National University of Singapore

Yes, but what I was getting at was that the target space was still a
MANIFOLD, not a bucket of dust or whatever. And it seems to me
[wrongly?] that in Ashtekarology, you play around with connections and
holonomies instead of metrics, but everything is still defined on a
manifold. So there does not seem to be any indication that spacetime
itself is replaced by anything.
Coming back to the metric, though: granted, Ashtekarology does not
prefer flat metrics. But what exactly happens to proper time?
Newsgroups: sci.physics
From: frisinv@alleg.edu
Subject: Axiom of Physics
Organization: Allegheny College
Date: Wed, 26 Aug 1992 17:49:22 GMT

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?
-----
Vince
Newsgroups: sci.physics
From: kim@Lise.Unit.NO (Kim Gunnar St|vring \yhus)
Subject: Old Articles.
Organization: Norwegian Institute of Technology
Date: Fri, 28 Aug 92 18:04:41 GMT

I need the articles on sci.physics between 18 june & 4 july.
How can I get them?

   Kim 0
From: andrew@rentec.com (Andrew Mullhaupt)
Newsgroups: sci.physics
Subject: Re: Axiom of Physics
Date: 1 Sep 92 00:25:15 GMT
Organization: Renaissance Technologies Corp., Setauket, NY.

In article <1992Aug29.165242.20599@murdoch.acc.Virginia.EDU> crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:
>In article <1217@kepler1.rentec.com> andrew@rentec.com (Andrew Mullhaupt) writes:
>>Whether you can have non-falsifiable statements in science is a function of
>>which philosophy of science you subscribe to. If every scientifically
>>meaningful statement is supposed to be falsifiable, then there are no axioms.
>
>     Why?  I don't see how an axiomatic basis prevents falsifiability.
How, for example does one possibly falsify the following (from Glimm and
Jaffe):

The pure states of a quantum mechanical system are rays in a Hilbert space H
(i.e. unit vectors with an arbitrary phase).

>     Also, presumably the theory derivable (not necessarily actually derived)
>     from an axiomatic basis (physically-based or not) is falsifiable.

But the hard core instrumentalist will not let you use any such axioms. Most
scientists are tolerant enough to include some non-falsifiable stuff, such as
the above postulate.

Later,
Andrew Mullhaupt
From: balbes@ohstpy.mps.ohio-state.edu
Newsgroups: sci.physics
Subject: Re: Axiom of Physics
Date: 27 Aug 92 09:55:05 EDT
Distribution: na

In article <25781@dog.ee.lbl.gov>, sichase@csa3.lbl.gov (SCOTT I CHASE) writes:
> 
> 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'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.

Mark Balbes
Xref: sparky sci.physics:14085 alt.sex:28353
From: ken@sugra.uucp (Kenneth Ng)
Newsgroups: sci.physics,alt.sex
Subject: Re: BAROMETERS (was Re: Subject?)
Date: 4 Sep 92 04:35:44 GMT
Distribution: na
Organization: Private Computer, Totowa NJ

In article <+sknkqn@lynx.unm.edu:, jfreter@triton.unm.edu (The Myth) writes:
: In article <ZOWIE.92Sep1122151@daedalus.stanford.edu> zowie@banneker.stanford.edu writes:
: >This whole thread reminds me of the age-old physics exam question:
: >You are taken to a large, impressive-looking office building.  You may
: >wander the building and its environs at will <etc. etc.> You are given
: >an accurate barometer.  Your task is to determine the height of the
: >building.
: >Name at least six ways to accomplish this task. [before breakfast! ;-]
: 2) climb to the top of the building.  Throw the barometer off and time how
: long it takes to hit the ground (really you should drop it). y=.5*g*t**2.

Only if your on the moon.  The atmosphere will limit terminal velocity and
therefore limit the acceleration.  But, I like your style :-)

-- 
Kenneth Ng
Please reply to ken@eies2.njit.edu for now.
Apple and AT&T lawsuits: Just say NO!
Newsgroups: sci.physics
From: xjeldc@lustorfs.ldc.lu.se (Jan Engvald LDC)
Subject: Re: Concern over radon levels?
Organization: Lund University
Date: Sun, 30 Aug 1992 22:26:52 GMT

>In article <geavdWa00WBNQ4_29l@andrew.cmu.edu> jw54+@andrew.cmu.edu (
Jonathan Wickert) writes:
>I'm in the process of buying a house in southwestern Pennsylvania.  As
>part of the home inspection, I had a radon test done by one of these
>companies that does radon testing for a living.  It involved placing two
>canisters in the basement, and one in the living room.  The canisters
>are removed after 3 days of exposure, and then sent to a central state
>licensed lab.
>
>The test revealed levels of 4.2, 5.5, and 7.6 picocuries/liter in the
>areas tested.  According to guidelines established by the EPA and the
>Center for Disease Control, a continuous exposure of 4 pCi/l is used as
>a guideline to indicate when some corrective action should be taken.
>
>My questions are
>
>1.  Are these levels sufficently high to be of concern?

Yes, I think so. Recently an investigation here in Sweden found that
the correlation between lung cancer and radon levels are linear down
to the lowest levels. There is no safe lower limit, except in the
sence that other things, like smokeing, may contribute more.

Radon houses are a big problem here. Some years ago there was a lot
of research done on how to lower the radon levels in existing
houses. Taken from memory the result was like this:

The source of radon can be either radiactivity in the building material
of the walls, or it comes from radioactivity in the ground.

In the fifties "blue light concrete" was a popular building material.
It took several decades until the radon problem with this material was
noticed. If you have such a house, there is not very much you can do
to lower radon levels. The only thing to do is to increase air circulation.
That can be very expensive! Your heating budget will increase a lot.
You can use heat exchangers, but that is not cheap either.
And the levels will not decrease that much ( 1/circulationincrease ).

For the case where radon comes from the ground several tricks were
tested. Most of them were rather expensive, like rebuilding part of
the house. There was one fix that was cheap, though. The good thing
was that it was the one that lowered the level the most, all the way
down to normal levels. It can be applied to houses that have a concrete
floor resting on the ground (very common here). A hole is done through
the concrete, a fan is mounted on top of it, and a pipe between the fan
and the outside prevents the radon from ever entering the house. The
low preasure below the concrete floor builds up a preasure gradient
in the floor, and the radon won't go up this gradient. Smart, isn't it!

_____________________________________________________________________________
Jan Engvald, Lund University Computing Center, Box 783, S-220 07 LUND, Sweden
Telephone: +46 46 107458, Telefax: +46 46 138225, Telex: 33533 LUNIVER S
E-mails: Jan.Engvald@ldc.lu.se,  xjeldc@seldc52,  psi%2403732202020::xjeldc
From: carlm@iplmail.orl.mmc.com (Carl Morris)
Newsgroups: sci.physics
Subject: Terminal velocity of a raindrop?
Date: 4 Sep 92 12:20:13 GMT
Organization: Martin Marietta

After reading some of the posts to this group I'm sure someone
out there can help me with my question: what's the terminal
velocity of a raindrop?