HDTenEightyP/NetNews huggingface dataset:
From: tjn32113@uxa.cso.uiuc.edu (Thomas J. Nugent)
Subject: Re: "What's New" July-24-1992
Organization: University of Illinois at Urbana
Date: Mon, 27 Jul 1992 23:15:27 GMT

matt@physics2.berkeley.edu (Matt Austern) writes:

>For myself, my opposition to the space station is because I would like
>to see a healthy space program (and yes, one that includes human
>flight, and probably one that includes a space station and a lunar
>colony), and it is my opinion that this particular space station is
>more likely to be detrimental to this goal than advantageous.  I
>believe that it would be better to cut our losses (perhaps with the
>shuttle as well), start over, and do it right.

I am also for a healthy space program, and I see your point that SSF might
be detrimental.  However, I don't think your proposed plan of action would
work.  If Freedom were killed, you would have a nearly impossible time
trying to convince Congress to fund another one.  It's also not guaranteed
that it could be 'done right.'  

It is my opinion that, while Freedom may be detrimental in some ways, killing
it would actually cause _much_ more harm than good.  Besides, we will be 
getting alot of very important info on the effects of weightlessness on
humans, which is necessary for human exploration of the solar system.

(Also, see my original post to the "What's New")

"Far better it is to dare mighty things, to win glorious triumphs, even
though checkered with failures, than to rank with those poor spirits who
neither enjoy nor suffer much, because they live in the gray twilight that
knows not victory nor defeat."
		- Theodore Roosevelt 

-- 
"To be average scares the hell out of me." -- Anonymous
Tom Nugent		e-mail: tjn32113@uxa.cso.uiuc.edu
From: jtwamley@physics.adelaide.edu.au (Jason Twamley)
Newsgroups: sci.physics
Subject: Re: non-orientable cosmology
Date: 28 Jul 92 05:57:28 GMT

U53644@uicvm.uic.edu writes:

>Regarding the speculation by G. Ellis that we are seeing the same galaxies
>multiple times due to light going around the universe more than once :

>Isn't there a result from General Relativity that holds that a photon can
>travel around the universe at most once before the universe collapses
>again ? (The version without the cosmological constant). So, if this is
>observed, does this kill off standard G.R. ?

>                                                  Joseph B. Dunphy


I believe that this result is only good for universes with compact spatial
sections with positive curvature...

Jason
From: sichase@csa2.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: Renormalization Group
Date: 31 Jul 92 18:55:46 GMT
Organization: Lawrence Berkeley Laboratory - Berkeley, CA, USA
Distribution: world,local
Reply-To: sichase@csa2.lbl.gov
NNTP-Posting-Host: 128.3.254.197
News-Software: VAX/VMS VNEWS 1.3-4   

In article <1992Jul30.150435@ece.arizona.edu>, nadar@ece.arizona.edu (Mariappan S. Nadar) writes...

>	I was wondering if someone could provide me with references to
>Renormalization Group theory in Statistical Physics.
> 
>	My knowledge in Physics is limited to the undergraduate curriculum
>in Engineering.

One excellent reference (which must be understandable because I read
it when I was an undergraduate myself) is "Renormalization Group
Theory" by Pfleuty and Tolouse.  I may not have gotten the title exactly
right or the spelling of the author's names perfectly correct.  But that
should be enough for you to track it down.

Although position-space renormalization group analysis is actually very
easy to understand, you need to have at least some understanding of
phase transitions and critical phenomena to understand the point of 
using PSRG in the first place.  I recommend Stanley's "Phase Transitions
and Critical Phenomena".

-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: hatay@spot.Colorado.EDU (Ferhat F. Hatay)
Subject: Re: Chaos
Organization: University of Colorado, Boulder
Date: Tue, 21 Jul 1992 17:46:53 GMT

Talking about the low-dimensional system: Can I bring the 
work of Glauser and his coworkers to your attention?
In this line of work, they use the Proper Orthogonal
Decomposition idea of Lumley to turbulent flows. 
POD modes are obtained either experimentally or numerically. 
Analysis reveal that it is possible to do a reconstruction
of the flow field using a finite number of POD modes. 
As this can be labelled as the "coherency" (here goes 
another vague term) in the flow field, dynamical 
evolution of these finite number of modes can be 
written an played with. 

Does anyone think this kind of work might provide a 
link between chaos and turbulence (in fluids) ?

-- 
Ferhat F. Hatay                        || Disclamer: |||||||||||||||||
Aerospace Engineering Sciences         || I speak for myself unless || 
University of Colorado, Boulder        || otherwise indicated.      ||
e-mail: hatay@spot.colorado.edu        |||||||||||||||||||||||||||||||
From: datkatz@scott.skidmore.edu (david atkatz)
Newsgroups: sci.physics
Subject: Re: Jacob's Ladders (was Re: What are those things called...)
Date: 24 Jul 92 20:17:47 GMT
Organization: Skidmore College, Saratoga Springs NY


	So far, in describing the operation of a Jacob's Ladder,
	two people have described the rising of the heated,
	ionized air as the mechanism for the heavenward rise
	of the spark. This is what I, too, have always believed.
	Recently, however, I was told that a Jacob's Ladder will
	work in the horizontal position as well, and thus this
	simple mechanism is not what causes the spark to move
	from narrow to wide gap.  I have never tried the experiment.
	
	Would some Ladder-possesing soul care to try this and
	report back?

	David
From: snarfy@cruzio.santa-cruz.ca.us
Newsgroups: sci.physics
Subject: Defining Photons
Keywords: Relating photons E=MC^2 criticism
Date: 26 Jul 92 09:00:44 GMT
Article-I.D.: cruzio.3942
Reply-To: snarfy@cruzio.santa-cruz.ca.us


In Messa:ge-ID:  <9935@sun13.scri.fsu.edu>  J.  A.  Carr  quotes  me  and
responds :


>>      Einstein,postulated that a photon has no  ``rest''
>>      mass.   We  are  faced  ,then,  with  the  task of relating these
>>      theoretical ``particles'' that do not have a rest masses  to  the
>>      equation E=Mc^2 since it is assumed that M represents a rest mass
>>      value.

>                  [ long argument based on wrong equation deleted ]

>The equation is
>                  E^2 = m^2c^4 + p^2c^2

>where m is the mass, p is the momentum (vector), E is the total energy,
>and c is the speed of light.  E=mc^2 is a specialized case of this
>equation, and can be used to tell you the total energy of a massive
>particle at rest.  It should not be applied to a massless particle
>such as a photon or neutrino.

>For massless particles, it is the case that E=pc.

       Your  criticism is noted and forwarded to my sources.  However my
       personal evaluation is that you are missing the point.  When  the
       word  ``particle''  is both applied to that which has no mass and
       to that which does have mass,  we  must  seriously  question  the
       choice of words used, for the sake of clarity ,if nothing else .

        We  are  not here trying to ``apply'' the equatiom E=Mc^2 to the
       photon. The stated purpose and idea  is  to  ``relate''  massless
       ``particles''  to  the  massive  ones  in the M of E= Mc^2 . If a
       photon has E and E has some relationship to M via E=Mc^2 (or  E^2
       =  m^2c^4  + p^2c^2) then there must some ``relationship'' that a
       photon  has  to  M  that  can  be  expressed  or  measured.   The
       expression  E=pc  contains no reference to M so that's one reason
       E=Mc^2 was used. The other reason is that we want E on  one  side
       of the equals sign and not E^2.

>I find it odd that someone can spend a lot of time working on such a
>document that was posted here and never take the time to read enough
>of Einstein to know the actual equations he used.

       If you are a college professor , the taxpayers  or  students  pay
       you to enlighten and clarify issues pertaining to your specialty.
       Why then have you not yet found a word other than ``particle'' to
       describe  that  which has no mass , to differentiate it from that
       which does?.  I think it's because some of you  would  prefer  to
       confuse people rather than teach them. The photon, as a concept ,
       would  be  more accurately described as a ``phenomena'' given the
       difficulty  you  have  manipulating  it  the  same   way   as   a
       ``particle''   mathematically.  (multiplying  by  zero  ,for  one
       thing).

      I find it odd that you have a job.

          Jim Ostrowski
From: macander@oasys.dt.navy.mil (Aleksander Macander)
Newsgroups: sci.physics
Subject: Re: density of commonly used materials
Date: 30 Jul 92 15:01:52 GMT
Reply-To: macander@oasys.dt.navy.mil (Aleksander Macander)
Followup-To: sci.physics
Distribution: usa
Organization: Carderock Division, NSWC, Bethesda, MD

In sci.materials, sundar@fiber-one.ai.mit.edu (Sundar Narasimhan) writes:
>Hi, I am interested in finding out the densities (ranges) of commonly used
>materials (starting from things like Aluminium, Steel, Wood etc. to
>rubbers and plastics). Is there a handbook of physical constants I can
>refer to? Is any such information available online?
>
>Thanks much.

Hi Sundar,
An excellent reference book that has all the information you need on
commonly used materials is MARKS' STANDARD HANDBOOK FOR MECHANICAL
ENGINEERS by Baumeister and al. This book should be readily available
in your MIT library.
Newsgroups: sci.physics
From: dwr2560@zeus.tamu.edu (RING, DAVID WAYNE)
Subject: Re: Aristotle and the Modern Physicist
News-Software: VAX/VMS VNEWS 1.41    
Organization: Texas A&M University, Academic Computing Services
Date: Tue, 28 Jul 1992 06:52:00 GMT

aephraim@physics.Berkeley.EDU (Aephraim M. Steinberg) writes...
>An amusing counterexample.  I should've been more careful about what I
>was saying; I meant that if a box starts with a well-defined center of
>mass, no evolution that is confined to the box and its contents will
>turn it into a state with a not-well-defined center of mass, which seemed
>to me to be the flavor of the original proposal.

I think you also want a well defined momentum. But then there's an
uncertainty relation... :-)

>%>I'd be slightly
>%>more inclined to believe that you could superpose two distributions with
>%>different QUADRUPOLE moments or something like that...

This is in fact what I had in mind. As I recall I worded my post
carefully to satisfy momentum cons and at the same time not confuse
the issue. I think the phrase was "move the masses around." Note the
plural. In hindsight I can see why that would be confusing.

>                                             Certainly, the cat alone is
>not in a coherent superposition, nor is the radioactive nucleus, taken
>alone, but together, they are.  (Assuming they have not yet interacted
>with anything else.)

Well, getting a cat into a pure state is quite an achievement! ;-)

Dave Ring
dwr2560@zeus.tamu.edu
From: jtwamley@physics.adelaide.edu.au (Jason Twamley)
Newsgroups: sci.physics
Subject: Re: Quantum Cosmological Boundaries and Determinisim?
Keywords: Quantum cosmology
Date: 23 Jul 92 10:10:42 GMT

Hi everyone...glad to see there are people interested in discussing these
topics...:

John and Stephen both emphasize the conditional probability interpretation
given to the density matrix or decohereing histories formulation of
quantum cosmology. However, in QM the density matrix contains not only our
ignorance of the details of the ensembe but also the QM uncertainty. Even,
if we can enumerate completely the position and momentum of every particle of
the tea and cup and surrounding enviroment to the limit imposed by the 
uncertainty principle we still cannot proceed deterministically... can we?
Also...when Steve admits a final and initial density matrix in the ADH what
exactly is fixed uniquely? Is it that collection of 
quasi-classical coarse grained histories which maximize the information 
content (ie. most finely grained histories compatible with quasi-classisity).
If this collection is not unique then we do not have complete prediction
of these histories. Also.. these histories presumably refer to suitably gross
collective coordinates ie. the path of a football through the air... if I
decide to ask ADH about the evolution of coordinates of a molecule of leather
in this football then ADH looses a degree of predictive power as we may be
going beyond that above mentioned  quasi-classically-optimised graining.


Jason

---------------------------------------------------------------------------
Jason Twamley                            | "WHY must I treat the measuring
Univ. of Adelaide Math. Physics          | device classically??  What will
GPO Box 498, Adelaide                    | happen to me if I don't??"
South Australia 5001                     |       -- Eugene Wigner
jtwamley@physics.adelaide.edu.au
From: jac@ds8.scri.fsu.edu (Jim Carr)
Newsgroups: sci.physics
Subject: Re: "What's New" July-24-1992
Date: 27 Jul 92 21:19:41 GMT
Reply-To: jac@ds8.scri.fsu.edu (Jim Carr)
Distribution: na
Organization: SCRI, Florida State University

In article <MATT.92Jul26223915@physics2.berkeley.edu> matt@physics.berkeley.edu writes:
>In article <JMC.92Jul26124213@SAIL.Stanford.EDU> jmc@SAIL.Stanford.EDU (John McCarthy) writes:
>
>> Did I misread, or did the physicists oppose the Space Station, rather
>> than just say that, considered as science, it wasn't worth the money?
>
>My impression is that physicists are essentially unanimous in thinking
>that the space station is worthless when considered as a scientific
>project.  There is no such consensus on whether or not it should be
>built, however---that depends on the individual's political views ....

Pretty accurate summary of the APS position.  Once it became clear that 
microgravity work was compromised by vibration, interest fell, and then 
I think those plans were dropped from the station altogether in the 
latest review of the project. 

But this thread is starting to miss a key point in the report from "What's 
News" concerning opposition to the current space station plan:  there 
were *75* _space_ scientists who wrote a letter in opposition. 

Many of those interested in exploring the universe are opposed to the 
latest plan for the space station because it will probably kill off 
major projects and delay others.  I am told that it already has affected 
some of the space science projects funded by NASA, but that is all 
third-hand from me.  Any of you sci.space folks out there?

--
J. A. Carr                                    |  "The New Frontier of which I  
jac@gw.scri.fsu.edu                           |  speak is not a set of promises
Florida State University  B-186               |  -- it is a set of challenges."
Supercomputer Computations Research Institute |   John F. Kennedy (15 July 60)
Xref: sparky sci.physics:11691 sci.research:838 alt.folklore.science:2805
From: oracle@cs.uow.edu.au (Oracle Manager)
Newsgroups: sci.physics,sci.research,alt.folklore.science
Subject: Re: Getting a PhD without being a grad student
Date: 27 Jul 92 01:25:20 GMT
Organization: Dept of Computer Science, Wollongong University, Australia

darice@yoyo.cc.monash.edu.au (Fred Rice) writes:
>Is this possible now?  Has anyone heard of someone earning their PhD
>through their own private research in, say, the last 30 years or so, the
>way Einstein did?

It certainly is. I have in my hot little hand a copy of the graduate
handbook for the University of Wollongong, and the regulations
covering PhD by publication comprises all of section III of the rules 
for doctoral degrees. And yes, a guy downstairs is getting a PhD this
way.
From: crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass)
Newsgroups: sci.physics
Subject: Re: Gyromagnetic ratio of the proton
Date: 27 Jul 92 20:47:59 GMT
Distribution: na
Organization: University of Virginia

In article <24945@dog.ee.lbl.gov> sichase@csa2.lbl.gov writes:
>In article <1992Jul27.191552.13679@unixg.ubc.ca>, leon@unixg.ubc.ca (Leon ter Beek) writes...
>> 
>>Can someone indicate where I can find an accurate number for the
>>gyromagnetic ratio of the proton in SI-units [1/s*T].   
>> 
>>Leon
>
>If it's not in the Review of Particle Properties, produced every other
>April by the Particle Data Group (most recently in PRD - blue cover),
>along with lots of other fun facts, then I'm stumped.  
>
>75% of everything interesting in the universe can be found in the little
>pocket version of that book.  90% can be found in the larger, full listings.
>An additional 5% is in "Inside Macintosh."   The last 5% is spread 
>pretty thinly... :-) 

     It is in the CRC Handbook of Physics and Chemistry.  It does
     not appear to be in my 1990 copy of the Review of Particle
     Properties.   

     Oh, the value (1986 recommended)

                    2.67522128(81) \times 10^8 1/(s T)

     It also does not appear to be inside the Macintosh downstairs
     (we had all the protons removed during the last maintenence).
     By the way, does anyone know how to put it back together ...

                               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
From: braham@physics.ubc.ca (Stephen Braham)
Subject: Re: Quantum Cosmological Boundaries and Determinisim?
Organization: University of British Columbia, Vancouver, B.C., Canada
Date: Thu, 23 Jul 1992 17:40:14 GMT

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

> [stuff deleted]

>classical mechanics).)  This is the basis of Hawking radiation and his
>later predictions that virtual black holes might make time evolution
>turn pure states into mixed states -- which he represents by a
>"superscattering operator".  This of course would seem to give an arrow
>of time.  Confusion reigns, as far as I'm concerned.

<grin>, a wonderful understatement :). Don Page recently gave a status
report on this stuff (actually, I heard the talk twice- once at
Banff, 2 months ago, and also last week, here at the UBC GR group),
and things have not improved, clarity-wise, since I was first in grad school.
The whole question is begging for an interpretation of quantum mechanics.
On top of that, the dynamics of BH radiation may be EXTREMELY dependent
on small scale effects (something I'm trying to work on now), and
they may NEVER mix the state.

			Steve
--
| Name: Stephen P. Braham | Perversion: Quantum Cosmologist|
| Hangout: UBC physics    | Signature:  Euclidean          |
|          Vancouver, BC  |--------------------------------+
|          Canada         | E-mail: braham@physics.ubc.ca  |
Newsgroups: sci.physics
From: bucknerb@bnr.ca (Brent Buckner)
Subject: Re: ***********MIND-BLOWING GEDANKENEXPERIMENT**********
Organization: Bell-Northern Research, Ontario, Canada
Date: Fri, 24 Jul 1992 17:01:44 GMT

In article <2377@nic.cerf.net> mitsu@nic.cerf.net (Mitsuharu Hadeishi) writes:
>
>I don't think anyone fully understood the import of the communication from Dr.
>Jack Sarfatti I posted a few days ago.  Let me summarize it first.
>

Is this the design from Physics Essays (vol 4, No. 3, Sept 1991)?

-- 
at Bell-Northern Research
voice:        (613) 765-2739
Canada Post:  P.O. Box 3511, Station C, Ottawa, Canada, K1Y 4H7
I do not claim that BNR holds these views.
From: jac@ds8.scri.fsu.edu (Jim Carr)
Newsgroups: sci.physics
Subject: Re: Gyromagnetic ratio of the proton
Date: 27 Jul 92 21:33:22 GMT
Reply-To: jac@ds8.scri.fsu.edu (Jim Carr)
Organization: SCRI, Florida State University

In article <1992Jul27.191552.13679@unixg.ubc.ca> leon@unixg.ubc.ca (Leon ter Beek) writes:
>
>Can someone indicate where I can find an accurate number for the
>gyromagnetic ratio of the proton in SI-units [1/s*T].   

Best source is Phys. Rev. D 45, S1 (1992) -- a special issue of 1 June 92 
containing the latest Particle Data Group review of particle properties.

The adopted magnetic moment of the proton is 2.792847386(63) (mu_N)

   (See page VIII.1 of the review)  This is the 1986 CODATA value.

The adopted value for mu_N is 3.15245166(28) x 10^{-14} MeV/T

   (See page III.1 of the review) This is based on the CODATA values 
   although some revisions due to much better data are under way. 
   Other citations are in the review.  You will have to convert it...
   (but e is 1.60217733(49) x 10^{-19} C)

Oh yes, numbers in parenthesis are the uncertainties in the last sig.figs.

--
J. A. Carr                                    |  "The New Frontier of which I  
jac@gw.scri.fsu.edu                           |  speak is not a set of promises
Florida State University  B-186               |  -- it is a set of challenges."
Supercomputer Computations Research Institute |   John F. Kennedy (15 July 60)
From: bweiner@ruhets.rutgers.edu (Benjamin Weiner)
Newsgroups: sci.physics
Subject: Re: Cost of public vs. private transportation
Date: 27 Jul 92 19:07:37 GMT
Organization: Rutgers Univ., New Brunswick, N.J.

>Many years ago, public transportation was profitable.  One of the
>problems that killed its profitability was regulation of fares.  It
>was always possible for a lawyer or politician to gain a reputation
>by fighting the evil railroads. [...]
>I would bet that public transportation is profitable in some parts
>of the world and even in some parts of the U.S.  Greyhound made
>money, at least until the bargain air fares came along.

I don't know why I get involved in these silly arguments but it
seems obvious to me that neither the old railroads (B & O, Penna.,
etc.) nor Greyhound are public transportation, given that they're
privately owned.  They are mass transit but the two aren't always
the same thing.  In that context, regulation of fares on the B & O
and setting the prices of, e.g., New Jersey Transit tickets ought to
be seeen as two different things.

Ben Weiner @exit9.turnpike.nj

Personal opinion only: Anyone who argues for privatizing Amtrak or
New Jersey Transit has never spent a lovely afternoon on the Garden
State Parkway.
Newsgroups: sci.physics
From: crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass)
Subject: Re: Gyromagnetic ratio of the proton
Organization: University of Virginia
Date: Wed, 29 Jul 1992 00:07:25 GMT

In article <1992Jul28.200456.13596@unixg.ubc.ca> leon@unixg.ubc.ca (Leon ter Beek) writes:
>>In article <1992Jul27.191552.13679@unixg.ubc.ca> I@unixg.ubc.ca wrote:
>>>
>>>Can someone indicate where I can find an accurate number for the
>>>gyromagnetic ratio of the proton in SI-units [1/s*T].   
>>
>
>Thanks to all who responded. The gyromagnetic moment of the proton is
>determined up to 7 significant figures to this date:
>
>gamma_p = 2.67522128(81) 1/(s T) )
>
>Leon

      Hate to be picky, but shouldn't there be a 10^8 somewhere?

                                  dale bass


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