HDTenEightyP/NetNews huggingface dataset:
From: dans@solbourne.com (Dan Scott)
Subject: Re: Wind Farms  
Organization: Solbourne Computer, Inc., Longmont, CO
Date: Wed, 9 Sep 1992 16:10:19 GMT

In article <1992Sep3.163534.28920@mcshub.dcss.mcmaster.ca> whitlock@dcss.mcmaster.ca (Jeremy Whitlock) writes:
>If I lived on a farm and had an acute love of the outdoors and the beauty of 
>unspoiled nature, the last thing I'd want is a matrix of ugly, noisy 
>wind turbines on my land, knocking down birds, spoiling my view, and generating
>electricity for the city folks.
>
	Are feedlots to be thought of as the beauty of unspoiled nature? Yet look
at all the farms with some sort of animal operation. The smell of manure, the 
sound of an oil well-head pump, the sound of a wind turbine are all associated
with money to the land owner. All these revenue generators can be viewed in a
positive frame when it is your bank account that is being increased. True, money
isn't everything, but then esthetics never paid the mortgage.

>Has any study been done that looks at what incentives would be needed to get
>farmers who think like this to change their mind?   Just how much money are
>we talking about here?
>
	Only 'gentleman farmers', who don't really need the revenue from their
land to survive, think that way.
> 
>
>-- 
>Jeremy Whitlock                 "My thoughts are mine, not Mac's"
>Dept. Engineering Physics
>McMaster University
>Hamilton, Ontario, Canada  


				Dan Scott
				Solbourne Computer, Inc.

Disclaimer: I'm not in a position to know Solbournes opinions,...yet.
From: mcirvin@husc8.harvard.edu (Mcirvin)
Newsgroups: sci.physics
Subject: Re: Question of Theory of Everything (or Grand Unified theory)
Date: 9 Sep 92 04:00:45 GMT
Article-I.D.: husc8.mcirvin.716011245
 <88251@netnews.upenn.edu> <8SEP199221412082@zeus.tamu.edu>

dwr2560@zeus.tamu.edu (RING, DAVID WAYNE) writes:

>Now you might think it astounding that you are alive at the same time as
>Witten (:-D) but that is not surprising either, because most of the people
>ever to have lived are alive today.

This has nothing to do with physics, but the statement "most of the
people ever to have lived are alive today" got debunked in a fairly
credible manner on alt.folklore.urban a while ago.

Still, there are certainly a lot of people around these days.
 
>Which reminds me... Consider Galileo, Newton, Einstein. There should
>be at least 3 people alive today as brilliant in physics as they were!

They're probably in real estate.

-- 
Matt McIrvin, Cambridge, Massachusetts, USA
From: palmer@sfu.ca (Leigh Palmer)
Subject: Re: George Brown (was It's Down to the Last Blank Check)
Organization: Simon Fraser University
Date: Sat, 12 Sep 1992 00:46:52 GMT

In article <10339@vice.ICO.TEK.COM> hall@vice.ICO.TEK.COM (Hal F Lillywhite)
writes:

>For those really interested in Congressman Brown's views (and we all
>should be since he has a *lot* of say in science funding) Try the
>Feb 92 edition of _Physics Today_, p38ff.  Brown participated in a
>roundtable sponsored by that magazine, which roundtable is therein 
>reported.  An interesting article in its own right.
>
>Of course we can also compare his comments speaking to scientists
>with what he told the general public in the letter in question.

I've not heard of this Brown fellow before, but I see that he's written a guest
editorial, "The Objectivity Crisis", in American Journal of Physics, September
1992, p. 779. I've not read it, of course, but I shall do so.

Leigh
From: beetle@cp1.uchicago.edu (Chris Beetle)
Newsgroups: sci.physics
Subject: Re: Wave/particle duality
Keywords: photon,particle,dual slits,interference,quantum waves
Date: 14 Sep 92 13:56:45 GMT
	    <xjeldc.41.716385288@lustorfs.ldc.lu.se>
Organization: University of Chicago, High Energy Physics

In article <xjeldc.41.716385288@lustorfs.ldc.lu.se> xjeldc@lustorfs.ldc.lu.se
(Jan Engvald LDC) writes:

>Is there any hard proof that such a spooky action occur (that one
>particle interferes with another particle sent through the double slit
>earlier)?
>
>It seems to me much more likely that the particle interferes with
>*itself*. This hypthesis should even be testable. Send one particle
>through each of a lot of double-slits.

	In the news article you submitted to sci.physics, you mentioned the 
possibility of conducting single-particle interference experiments.  The 
problem is that most of the particles of nature are so darned small (in mass,
that is) that they couldn't really be well enough locallized to do the 
experiment.  But, within the last ten years or so, the technology became 
available and single particle interference experiments were performed with 
slow neutrons.

	A crystal was used with four raised ears.  The first ear would split
the neutron into two paths.  The second and third lay along the split paths
and refocussed the neutron on the fourth ear which recombined them.  The
aparatus as a whole was large enough to allow separate manipulation of the
split neutron beams, so interference was possible.  The wave packet for a
neutron is ~1 cm across and .01 cm in length so the incident neutron flux on
the apparatus could be lowered enough to have one neutron present in the
apparatus most of the time.  By the way, the experimenters did find exactly
the sort of interference quantum mechanics predicts.

	I read about this junk in a review article:
Greenberg, D.M.: Rev. Mod. Phys. 55, p. 875    (1983)

				-- Chris Beetle (beetle@hep.uchicago.edu)
From: matt@physics.berkeley.edu (Matt Austern)
Newsgroups: sci.physics
Subject: Re: Question of Theory of Everything (or Grand Unified theory)
Date: 9 Sep 92 19:22:32 GMT
	<88251@netnews.upenn.edu> <8SEP199221412082@zeus.tamu.edu>
	<26180@dog.ee.lbl.gov>
Reply-To: matt@physics.berkeley.edu
Distribution: na
Organization: Lawrence Berkeley Laboratory (Theoretical Physics Group)
NNTP-Posting-Host: physics.berkeley.edu
In-reply-to: sichase@csa2.lbl.gov's message of 9 Sep 92 19:56:56 GMT

In article <26180@dog.ee.lbl.gov> sichase@csa2.lbl.gov (SCOTT I CHASE) writes:

> Galileo and Newton were bright, but they were also lucky to be born when 
> you could gain fame and fortune for say, looking through a telescope
> and discovering sun spots, moons, etc.

I think that this is an unfair characterization of Newton, at least.
Remember: he had to invent new mathematical tools to do the
calculations that were necessary for his work in theoretical physics.
It is not obvious that the gravitational field of a spherical body is
the same as the gravitational field of a point particle located at
that body's center, and, in Newton's day, that calculation was
decidedly nontrivial.  It was also nontrivial to prove that Newtonian
gravitation yielded Kepler's laws for planetary orbits.  And while
Newton's laws of motion didn't require any stunning feats of
mathematical virtuosity, they did require the introduction of several
new and abstract concepts---again, a great achievement.

Einstein's opinion was that Newton was the greatest physicist who ever
lived, and you can make a very good case that he was right.  I
certainly can't think of any other single individual who contributed
so much to the field.


--
Matthew Austern                   Just keep yelling until you attract a
(510) 644-2618                    crowd, then a constituency, a movement, a
austern@lbl.bitnet                faction, an army!  If you don't have any
matt@physics.berkeley.edu         solutions, become a part of the problem!
From: mcirvin@husc8.harvard.edu (Mcirvin)
Newsgroups: sci.physics
Subject: Re: Why do protons outnumber antiprotons?
Date: 4 Sep 92 21:29:39 GMT
Article-I.D.: husc8.mcirvin.715642179

ric@hpspdla.spd.HP.COM (Ric Peregrino) writes:

[about the hole theory of electrons and positrons]

>Scott Chase:

>>beta decay:  n -> p + e + nu.  How does your picture account for
>>the production of an electron without leaving a positron around somewhere?

>Well,,, I really don't know! But for one, this situation includes more
>than just electrons and positrons. For two, it does leave an (?) anti-
>electron neutrino around. For three, is energy not conserved in beta decay?
>If it is then the overall picture remains the same: no imbalance of energy
>results and total particle energy plus total anti-particle energy remains
>constant. Or doesn't it?

The correct formulation, using field theory, still has conserved
quantities, like energy and (here, at least) lepton numbers; the
electron antineutrino accounts for conservation of electron number
when the electron is produced.  What you described, though, involves
the machinery of a completely filled sea of negative energy electrons,
and describes pair production as the elevation of a negative-energy
electron to a positive-energy state, leaving a "hole."  That can't
account for beta decay, since the thing that's produced along with
the new electron is not a positron but an antineutrino.  A theory
in which the creation and destruction of particles depends on this
kind of particle-hole creation leaves no room for differences in
the kinds of holes left behind by a particular particle.

The hole theory was a good one, and worked well for a while.  It
eventually ran up against problems like this one, and many others;
around the 1940's or so it gave way to the more modern formulation
in which the equation of motion describes not a wave function
but a field, whose excitations are particles.
 
-- 
Matt McIrvin, Cambridge, Massachusetts, USA
From: matt@physics.berkeley.edu (Matt Austern)
Newsgroups: sci.physics
Subject: Re: What do we know about choice of groups?
Date: 10 Sep 92 23:13:27
Organization: Lawrence Berkeley Laboratory (Theoretical Physics Group)
Reply-To: matt@physics.berkeley.edu
NNTP-Posting-Host: physics.berkeley.edu
In-reply-to: matmcinn@nuscc.nus.sg's message of 11 Sep 92 02:15:51 GMT

In article <1992Sep11.021551.1744@nuscc.nus.sg> matmcinn@nuscc.nus.sg (Mcinnes B T (Dr)) writes:

> Suppose that the standard theory is right, and that the gauge group of
> the world is "SU3xSU2xU1"  [actually S[ U2xU3 ] of course]. Then we will
> have to understand why this particular group was chosen from infinitely
> many others. The same problem arises, albeit less urgently, if GUTs are
> correct: why SO[10]  [actually Spin[10] of course]  rather than SO[110]
> ?
> What ideas have been proposed to solve this problem? 

Well, one constraint that most theorists believe in is that a gauge
theory has to be anomaly-free.  I really don't feel like explaining
what that means just now; for the moment, let's just say that it is a
technical property which is necessary for the theory to be
renormalizable.  This excludes most possible gauge groups---still
leaving an infinite number, but a much smaller infinity than without
that constraint.  

We can hope that by imposing other physical principles, we might be
left with fewer possibilites---ideally, only one.  String theorists
have some optimism along those lines.


--
Matthew Austern                   Just keep yelling until you attract a
(510) 644-2618                    crowd, then a constituency, a movement, a
austern@lbl.bitnet                faction, an army!  If you don't have any
matt@physics.berkeley.edu         solutions, become a part of the problem!
Xref: sparky sci.physics:14128 alt.sex:28388
From: purp@wixer.cactus.org (Jim Meyer)
Newsgroups: sci.physics,alt.sex
Subject: Re: BAROMETERS (was Re: Subject?)
Date: 4 Sep 92 16:59:32 GMT
Distribution: na
Organization: Real/Time Communications

In article <ZOWIE.92Sep1122151@daedalus.stanford.edu> zowie@banneker.stanford.edu writes:
>Lots of people write:
>	<stuff about people foolishly jumping out of windows>
>
>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! ;-]

Ok, here goes:

1) Take the barometer to ground level. Record reading. Take the
barometer to the top of the building, evading suicide-fearing armed
guards. Record reading. Perform amazing physics equation I never
bothered to learn involving the difference in the readings. Record
height.

2) Take the barometer to the top of the building, with armed guards in
tow. Drop barometer. Record the time it takes for the barometer to hit
the ground. Multiply by the constant for speed of falling objects.
Record height. BONUS: Perform an experiment to test the constant; drop
an armed guard at the same time and notice whether they hit the ground
at the same time.

3) Take the barometer to the landlord of the building. Offer the
landlord your fine barometer in exchange for telling you the height of
the building.

4) Take the barometer to the landlord of the building. Threaten to beat
the landlord with said barometer if he/she doesn't tell you how tall the
building is.

5) ObSex: Go to the landlord. Sleep with him/her for the information.
Make a gift of the barometer for the fine evening you spend.

6) Sell the barometer. Buy a really long tape measure. Measure building.

Good 'nuff?

--Purp, non-fizzical.
-- 
+---------------+------------------------------+-----------------------+
| Jim Meyer     | If I express an opinion, you | purp@wixer.cactus.org |
| Austin, Tejas | can bet no one else agrees.  | DoD#0680 LiveToFlame! |
+---------------+------------------------------+-----------------------+
From: sichase@csa2.lbl.gov (SCOTT I CHASE)
Newsgroups: sci.physics
Subject: Re: Question of Theory of Everything (or Grand Unified theory)
Date: 8 Sep 92 18:41:46 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 <1992Sep8.023027.15883@nuscc.nus.sg>, matmcinn@nuscc.nus.sg (Mcinnes B T (Dr)) writes...
>Please excuse me if you have already debated the hell out of this
>one......but I would like to make the following observation. It strikes
>me that [eg] superstring theory is not easy to understand. Suppose that
>in the 80's it had turned out that string theory is right. Then we would
>have to conclude that the universe is incomprehensible to all of
>humanity except for a tiny coterie of people. Now: is it not truly
>astounding that the complexity of the universe is so precisely
>calibrated to the intelligence of homo sapiens? So that it is just
>barely within our comprehension, to the extent that a few hundred of us
>can understand it? Aren't we lucky? Would one not expect a priori that
>the universe should be either easily comprehensible to all, or vastly
>beyond the intellect of even a Fields medallist?  :)

I suspect that it's more a matter of education than inborn intelligence.
As a society, we judge high energy physics sufficiently important that a 
few thousand people get well-educated in it.  Many more certainly could
do so, if it turned out that such knowledge was prerequisite to economic
survival, for example.

There is also a matter of assimilation.  Many people, future lawyers and 
doctors, for example, take the time to take a modern physics course as 
undergrads, in which they are exposed to the routine concepts of SR and QM,
which would have been out of bounds for such a student fifty or more years
ago.  It takes time for ideas to be digested by the broader physics and 
education communities, for the simple examples and thought-experiments 
to be perfected and for the essence of what needs to be taught to be 
developed.  If string theory were to be proven with the same weight of
experiment that SR is founded upon, then I expect that ten or twenty years
later, the rudimentary concepts of string theory would be standard 
undergraduate fare.

-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: flower@hpcc01.corp.hp.com (Graham Flower)
Date: Thu, 10 Sep 1992 15:50:48 GMT
Subject: Re: It's Down to the Last Blank Check
Organization: the HP Corporate notes server
Newsgroups: sci.physics



    It seems to me that "carte blanche' overstates things a bit. I dont follow
    these things very closely, I dont work in a National lab or in Government
    sponsored research, but articles I've seen in things like the Harvard 
    Business Review have given me the impression that the percentage of 
    research supported by government in the US has been in decline for 30 years.
    The numbers I recall are a slippage from 67% of all research being gov 
    funded to 44% being gov funded. Considering that things like Nasa's budget,
    are on the order of 10-20 billion a year, I find it hard to believe that
    such expenditures are burdensome, and in any case I wouldnt describe it 
    as a blank check. Bear in mind that the Government now spends something 
    like 900 billion in direct payments to individuals, 250 billion in defense
    and total expenditures are on the order of 1500 billion. 

       Another thing that is interesting to note is that steep declines in 
    government sponsored research occurred at a time when the ecomomy was at
    its Zenith, very low iunemployment and good growth and profitability. 
    (specifically 1965-1970). A bit curious dont you think? 




Graham Flower ms 90-TT               |  Better to have convictions and act on 
Hewlett-Packard  350 W Trimble Rd    |  them, even if they are wrong, than to  
Microwave Semiconductor Division     |  waffle in indecision.
San Jose, California, 95131          |
 graham_flower@sj.hp.com             |
From: mcirvin@husc8.harvard.edu (Mcirvin)
Newsgroups: sci.physics
Subject: Re: Uncertainty Principle [T.Bollinger => LONG]
Date: 5 Sep 92 16:05:57 GMT
Article-I.D.: husc8.mcirvin.715709157

terry@aslws01.asl.dl.nec.com (Terry Bollinger) writes:

>THE FOURIER TRANSFORM INTERPRETATION OF QUANTUM UNCERTAINTY

[nice explanation thereof deleted]

This is the right way to see the existence of an uncertainty principle
*for position and momentum*.  For other things, such as various
components of spin, this kind of picture no longer works.  Remember that
the spatial wave function, with its single phase and amplitude, describes
only the spatial degrees of freedom of a particle; to describe spin you
have to put a spinor into the wave function as well, and then you can
get uncertainty relations that have nothing to do with Fourier duality.
The important thing is that the associated operators don't commute.  What
you've really shown is that the position and momentum operators don't
commute, but there are other kinds of non-commutation as well.
 
>SIZE ASYMMETRY OF MATTER IN SPACE/MOMENTUM UNIVERSES

>The two relationships are seen in the size of our universe.  If you truly
>tried to build a universe that was "symmetrical" in its distribution of
>paticle memberships between Space space and Momentum space, it would
>instantly go ka-BLOOEY and expand drastically into the Space side of things.
>Why?  Because it's cheaper that way -- the long intial corkscrews in Momentum
>space would act like very energetic springs trying to collapse back together,
>and in the process of doing so they would cause an explosion in the no-cost-
>to-expand corkscrews of regular Space.

I'm not sure about this bit.  Remember that although the universe is
very large, most of the matter in it is fairly well-localized-- the
wave functions of electrons are a few Angstroms big, and those of
nuclear particles are smaller still.  The key is that in a bound system,
like an atom or a nucleus, there *is* a cost associated with spreading in
position space-- it's the binding energy.
 
-- 
Matt McIrvin, Cambridge, Massachusetts, USA 
Newsgroups: sci.physics
From: pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt)
Subject: Re: Computability of the universe
Organization: Computer Science Department,  Stanford University.
Date: Fri, 11 Sep 1992 20:34:37 GMT

In article <BuFCLA.958@dcs.glasgow.ac.uk> jack@dcs.glasgow.ac.uk (Jack Campin) writes:
>This should hardly come as a surprise if you remember that an optical
>system can do Fourier transforms in constant time.

A prism analyzing a slit of light computes a Fourier transform, but
that's not what is usually being referred to when this oft-heard claim
is made.

What an optical system computes, to a first approximation, is the
convolution of a planar 2D scene with a point spread function.  When
the PSF is a delta function the image is the scene, in perfect focus.
This occurs for an ideal lens with monochromatic light and with the
image plane at the focal plane.  In any other situation the PSF
broadens, blurring the image.  The PSF can be found as the image
resulting from a scene which is a delta function, i.e. a point of
light.  (This first approximation ignores chromatic aberration,
interference, diffraction, polarization, etc., none of which fit this
convolution picture quite so neatly.)

A typical place for the Fourier transform to enter this picture is when
we come to compute the convolution in the process of simulating the
system's behavior.  The lens itself can compute the convolution in real
time because it does so in parallel.  But when the simulation is run on
a sequential computer, convolution slows down to an O(n^2) process for
n pixels.  It often turns out to be faster to compute the convolution
by first Fourier transforming both the scene and the PSF into spatial
frequency space O((n log n)), taking the pointwise product of the
results (O(n)), then transforming back out of frequency space (O(n log
n)).

There are also other reasons to be interested in representation of the
image in the spatial frequency domain.  However at no time does the
optical system care about any of those reasons, and it does not do
anything on its own initiative that could be described as a Fourier
transform, other than chromatic aberration.

-- 
======================================================| God found the positive
Vaughan Pratt   pratt@cs.Stanford.EDU   415-494-2545  | integers, zero was
======================================================| there when He arrived.
From: matmcinn@nuscc.nus.sg (Mcinnes B T (Dr))
Subject: Re: Supersymmetry joke
Organization: National University of Singapore
Date: Mon, 14 Sep 1992 05:33:05 GMT

allenk@molest.ugcs.caltech.edu (Allen Knutson) writes:
: Ascribed to Don Finnell:
: 
: "What do you mean, no evidence for supersymmetry? They've already found
: half the particles!"

	What, no sleptons?                                             : 
Newsgroups: sci.physics,sci.math,sci.logic