Newsgroup sci.physics 203569

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Richard Andrew Bryan (bryanr@ecf.toronto.edu) wrote:
: You are indeed correct.  I read in an issue of "popular Mechanics" that
: the speed of light is indeed a limit (in the sense of calculus) meaning
: that the velocity can be approached from both sides but never reached.  At
: the speed of light mass becomes undefined or infinite.  At subluminal
: speeds mass is a positive quanitiy while at superluminal speeds, mass
: becomes a negative quantity.  The problem is that negative mass hass never
: been found and that negative mass would imply negative energy.  These
: theories need more discussion. 
I was under the impression that some effects had been observed which, 
according to our present models, should indicate negative energy densities.
: Richard Bryan (MECH 9T7)
: On 20 Oct 1996 atwilson@traveller.com wrote:
: > In <3262a326.23679365@news.villagenet.com>, aklein@villagenet.com writes:
: > >Tardyons, of course.  Tachyons have to be slowed to the speed of
: > >light.
: > 
: > I was under the impression that tachyons went faster than light in their
: > medium by definition. If they were slowed down, then they would no longer
: > be tachyons. - I think.
: > 
: > ATW
: > 
: > 
: > 
--
---------------------------+--------------------------------------------------
Ring around the neutron,   |  "OK, so he's not terribly fearsome.
A pocket full of positrons,|   But he certainly took us by surprise!"
A fission, a fusion,       +--------------------------------------------------
We all fall down!          |  "Was anybody in the Maquis working for me?"
---------------------------+--------------------------------------------------
"I'd cut down ever Law in England to get at the Devil!"
"And what man could stand up in the wind that would blow once you'd cut 
down all the laws?"
------------------------------------------------------------------------------
This message may not be carried on any server which places restrictions 
on content.
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e-mail will be posted as I see fit.
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meron@cars3.uchicago.edu (Mati Meron):
>:-))))))))))))))))))))
	Just as I suspected -- Mati is a grinning idiot.
-- moggin

Ken Fischer (kfischer@iglou.com) wrote:
: : In article  
: : Anthony Potts  writes:
: : >
: : >Well, I believe that diamond has a refractive index of around 10, and that
: : >this is pretty much as high as it gets. This means that light in diamond
: : >travels at one tenth of its speed in a vacuum.
:        Diamond has a "hardness" of 10.0, but I doubt if
: the index of refraction is an integer number, hardness is
: an integer number for diamond because diamond is the
: hardest material known, and 10 is defined as the upper 
: limit, with corundum (aluminum dioxide?) being assigned
: the number 9, and no other natural occurring elements
: or compositions are above 9.
The refractive index of diamond is almost exactly the same as that of 
pure water, which is pretty high but nowhere near 10.
Corundum is a natural mineral, in fact it is the crude form of the same 
mineral that forms rubies and sapphires if it has formed good crystals 
with the correct contaminants.  As I recall, it is chemically related to 
aluminum oxides, but has a different structure than the abrasive known as 
alox.
--
---------------------------+--------------------------------------------------
Ring around the neutron,   |  "OK, so he's not terribly fearsome.
A pocket full of positrons,|   But he certainly took us by surprise!"
A fission, a fusion,       +--------------------------------------------------
We all fall down!          |  "Was anybody in the Maquis working for me?"
---------------------------+--------------------------------------------------
"I'd cut down ever Law in England to get at the Devil!"
"And what man could stand up in the wind that would blow once you'd cut 
down all the laws?"
------------------------------------------------------------------------------
This message may not be carried on any server which places restrictions 
on content.
------------------------------------------------------------------------------
e-mail will be posted as I see fit.
------------------------------------------------------------------------------

zeleny@oak.math.ucla.edu (Michael Zeleny):
>>>A veritable polymath, your frere Jacques.  I expect the sci.physics
>>>crowd to take special pleasure in this quotation.  [...]
moggin@bessel.nando.net (moggin):
>>Not to dampen their fun, but it might be better if they knew that
>>you misattributed both of the quotes.
meron@cars3.uchicago.edu (Mati):
[to Zeleny]
>You bet.  Best laugh I've had in a long, long time. [...]
[to Silke]
>I was chuckling at the statement " ...With Einstein, for example, we
>see the end of a kind of privilege of empiric evidence".  It is quite
>the opposite, in fact.
	Then again, we can see that at least one physicist doesn't
especially care.
-- moggin

In article <54ggon$6mm@hawk.ee.port.ac.uk>, Gel6036@port.ac.uk (Chris
Mills) wrote:
> In article ,
billa@znet.com (Bill Arnett) says:
> >
> >Maybe the USA should make a deal with the rest of the world:  we'll go
> >metric if you'll learn to speak English.  (This is only half joking; I
> >think both would be big wins for the world as a whole.)
> >
>  
> You Yanks don't speakor write proper English ...
Maybe not but we do manage to communicate with our British friends.  The
grammarians can argue about the fine points but the rest of us seem to get
along just fine.
But the same cannot, obviously, be said for the rest of the world.  I can't
communicate with anyone who doesn't speak one of the languages I happen to
know (and that is a damn short list :-(  )   Obviously, life would be a lot
easier if everyone had one language in common (but not necessarily to the
exclusion of other additional languages).  English, despite its
multitudinous faults, is probably the most widely spoken language at the
present time and hence the natural choice as the standard.  I would
actually prefer Esperanto or some other conciously designed and regular
language but English will do.
-- 
Bill Arnett     billa@znet.com       http://www.seds.org/billa/
"I know that I am mortal and the creature of a day; but when I
search out the massed wheeling circles of the stars, my feet no
longer touch the earth, but, side by side with Zeus himself, I
take my fill of ambrosia, the food of the gods." -- Ptolemy

For years my high school students have been telling me that if you 
drop a penny from the top of the Empire State Bldg, by the time it 
reaches the ground it will be going fast enough to kill someone.
Is this true or is it just one of those beliefs (like the direction of 
the spin in an emptying toilet bowl depending on your hemisphere) that 
is not based on fact?
I would think that the penny would reach terminal velocity, due to air 
resistance, pretty quickly.  I do not know how quickly, or what the 
terminal velocity is.  Is there some way to calculate the theoretical 
terminal velocity of a flat disk like a penny?  I realize that dealing 
with air resistance and a spining disk is not a trivial problem.  In 
high school physics we almost completely ignore air resistance. I 
would like to be able to give my students a correct answer to their 
question.  Any suggestions as to how we could determine the velocity 
of a penny dropped from the top of our school building?
Any help would be appreciated.
Thanks,
Pat Clark

In article <54goqo$9i@fremont.ohsu.edu>,   wrote:
>This is a multi-part message in MIME format.
>
>
>if I may comment,
>    
>    I don't believe, and if you were to perhaps review the 'origin of 
>species', that Darwin meant as much strength,as you see it,as the main 
>criteria for the success of a species, but more the ability to reproduce 
>more frequently and with a lower infant mortality rate.
Abian answers:
 With all the profound and ingenious observations, Darwin still believed
and professed that  THERE IS A NATURAL SELECTION  ADMINISTERED AND
PERFORMED BY NATURE.
 No place in his writing did Darwin raise  a fist of defiance and said 
"Natural Selection may  govern the animals who do not have the intelligence
 of  mankind - But mankind will not allow Nature govern mankind - because
 mankind with its intelligence and technology will dictate conditions
 for the survival of mankind above any other species!!!!"
 And no place in his writings did Darwin say that "We will alter the
nature and we will impose our selection - definitely   GIVING 1OO%
priority on the survival of HOMOSAPIENS!!!!  
According to Darwin a child born with a congenital fatal heart
disease  will be eliminated by NATURAL SELECTION - that  child is a
weakling and will be eliminated according to the Natural Selection.
But we  say NO, No, No .  We will install an artificial heart which
will probably function better than any natural heart  and save the
child!!
 So, Darwin, with all his  contributions, injects a note of surrender
to the vicious, cruel and  naferious (FOR HOMOSAPIENS) Nature.
 Now, where the PEARCE VACCINE comes?  It comes to prevent the
homosapiens to annihilate each other - there is where the PIECE VACCINE 
comes.  Because, due to our science and technology, Homosapiens  will
become perhaps the strongest species - the danger is that they may 
slaughter each other (as the past and present history shows)  and there
is where we need the PIECE VACCINE  to prevent homosapien-self-distraction.
-----------------------
  The origin of species by means of natural selection, or the preservation
  of favoured races in the struggle for life.  C. DARWIN  (1859)
 The future of species by means of rational alteration of Cosmos, or the
 preservation of intelligent races in the struggle for life. A. ABIAN (1992)
-- 
--------------------------------------------------------------------------
   ABIAN MASS-TIME EQUIVALENCE FORMULA  m = Mo(1-exp(T/(kT-Mo))) Abian units.
       ALTER EARTH'S ORBIT AND TILT - STOP GLOBAL DISASTERS  AND EPIDEMICS
       ALTER THE SOLAR SYSTEM.  REORBIT VENUS INTO A NEAR EARTH-LIKE ORBIT  
                     TO CREATE A BORN AGAIN EARTH (1990)

In article <54fu43$985@newsbf02.news.aol.com>, LBsys  wrote:
>Im Artikel <54erk4$4hh@news.iastate.edu>, abian@iastate.edu (Alexander
>Abian) schreibt:
>
>>you know
>>very well what do I mean - 
>
>Well, there was no intention to get you wrong on my side, sorry...
>
>>I mean that those people who are opposed to 
>>Genetic Engineering - they  are surrendering to a cruel and nefarious
>>Natural Selection principle! arguing that one must not tamper with the 
>>Nature !!!
>
LBsys writes:
>Aha. I didn't suspect this at all, but I do understand now, that you are
>under the impression, that we are able to engineer all sorts of nice
>vaccines for every grievance known to mankind. Up to this day mankind has
>always succeeded in using any inventions as much for the bad as for the
>good. Find a "vaccine" against that first, is my suggestion.
>
Abian answers:
 That is precisely the aim of the PEACE VACCINE.  To  create the healthiest
the strongest species of homosapiens with aggressive intellectual abilities,
who will achieve greater and greater scientific, technological, genetic,
art, etc., etc conquests  AND WILL BE AT PEACE WITH EACH OTHER.  Since the
past and present history shows that  war-mongering, ware-waging, manslaughter,
racists and genocidal tendencies still are a deeply-seated trends in human
psyche - to produce  A PEACE VACCINE must be the most urgent item for
biologists, geneticists and the whole world population.
--------------------------
  The origin of species by means of natural selection, or the preservation
  of favoured races in the struggle for life.  C. DARWIN  (1859)
 The future of species by means of rational alteration of Cosmos, or the
 preservation of intelligent races in the struggle for life. A. ABIAN (1992)
-- 
--------------------------------------------------------------------------
   ABIAN MASS-TIME EQUIVALENCE FORMULA  m = Mo(1-exp(T/(kT-Mo))) Abian units.
       ALTER EARTH'S ORBIT AND TILT - STOP GLOBAL DISASTERS  AND EPIDEMICS
       ALTER THE SOLAR SYSTEM.  REORBIT VENUS INTO A NEAR EARTH-LIKE ORBIT  
                     TO CREATE A BORN AGAIN EARTH (1990)

> You're claiming that your pet theory's predictions are consistent with
Tuft
> data, but you don't have figures in front of you?
> 
I once thought of the following:
The frequency shifting in sound waves is certain, but what if it doesn't
apply to light? 
If frequency shifts proportional to the distance light travels, we would
observe that the more distant stars are the more shift in frequency, just
like we do today?

Lloyd R. Parker (lparker@larry.cc.emory.edu) wrote:
: Mark Brindle (brindle@lf.hp.com) wrote:
MB: Yes, Lloyd, that *IS* what you said;  and furthermore, you said
MB: that Planck's equation could be used to predict the *energy* of
MB: of a radiator (i.e., in Joules) WITHOUT RESPECT TO TIME.
MB: 
MB: Only one problem, Lloyd -- that's ABSOLUTELY 100% DEAD WRONG!
MB: Planck's equation tells you *nothing* about the "energy of a
MB: black body radiator" -- because, there is *NO SUCH THING*.
LP: Well, I guess Wall doesn't know that -- he derives Planck's equation in 
LP: terms of energy.  I guess Strobel doesn't really know that either, since 
LP: he used the phrase "energy" or "distribution of energy" and "total 
LP: energy" and "radiate more energy," etc., repeatedly.
Lloyd, *your* inability to understand what Planck, Wall, and Strobel
are saying has absolutely no effect on physical reality -- any more
than your moronic proof-by-strenuous-assertion that "toque = work".  
Only in this case, there is *NO EXCUSE* for *anyone* with even an
associate degree in the physical sciences for getting it wrong.
Just *LOOK AT THE FRIGGIN' UNITS* in the Planck equation -- or ask
a bright 10th grader to explain the difference between "extensive"
and "intensive" properties.  Duh!
The *SIMPLE FACT* is that light bulbs are rated in *WATTS* and NOT
in Joules.  Why?  Because there is *NO SUCH THING* as "the energy
of a radiator".  But pardon me, your total ignorance of such things
obviously *proves* that chemists don't need to know the difference
between energy and power.  So sorry, my mistake.
MB: I'll give you a hint, Lloyd.  Radiators CANNOT be characterized
MB: in terms of "Joules" -- the very idea is absolute nonsense.  Of
MB: course, that doesn't prevent you from *again* making the claim.
LP: Wall shows the equation in ergs/cm^3 -- energy density -- remember?
Guess what, Lloyd?  Ergs/cm^3 is *NOT* a unit of energy;  the *erg*
is a unit of energy -- you CAN'T just ignore the "/cm^3" part.  Duh!
As I've already explained in great detail, *IN THIS CASE*, erg/cm^3
is a direct measure of radiated *power*.  Anyhow, *you* claimed that
Planck's equation yields units of Joules/m^2 -- which is absolutely
DEAD WRONG in *every* case.  (Want me to cite the DejaNews entry?)
LP: Gee, Mark, I thought we were making progress in your therapy here, and 
LP: now you've gone and regressed.  But at least you aren't blathering about 
LP: there not being gravitational energy anymore, so maybe we are making some 
LP: progress.
Shoulda left that one alone, Lloyd.  The subject came up when *YOU*
made the idiotic claim (in a context of *purely* Newtonian physics)
that gravity "must supply energy" to maintain the *force* of a log
leaning on a wall.  That's right, Lloyd, YOU personally discovered
the "missing link of Newtonian physics" -- The Joules Of Gravity!
Hey, but no surprise -- you discovered *LOTS* of equally amazing
stuff such as The Joules Of Power and The Joules Of Torque.
It was only when a net.cast-of-thousands mocked the utter stupidity
of your "gravity must supply the energy" claim that you attempted
to throw up a smokescreen by babbling about "gravitons" and such.
DejaNews and I would be *delighted* to refresh your memory, Lloyd.
Oops, how clumsy of me again!  Your total ignorance of such things
obviously *proves* that chemists don't need to know the difference
between energy and force...
...so sorry, my mistake,
Mark
      "And oftentimes excusing of a fault
       Doth make the fault the worser by th'excuse."
                              -William Shakespeare

We, too are using FreeMail Internet Express, however, our 
set-up uses the SMTP version, not the UUCP version. We 
have not had any problem with it at all.
It has let us set up e-mail accounts for about 200 employees 
who work at various locations, here on campus, and off 
campus.
They are able to send / receive e-mail and files through a 
Freemail server. People here on campus connect via the 
LAN, and off-site people connect by dialing into a 
dedicated modem. All connections are store-and-forward, 
so there is just short connection times.
It actually is a plus to us that they can not browse the web 
with FreeMail. Has totally solved our problem of giving 
unlimited e-mail access but limit total connection time for 
hourly employees, etc.
They have posted a lot of different versions, and they have 
told me more is on the way  (Freemail is the company that 
wrote the 'new way to office' Kinkonet software for 
Kinko's Inc.).   The web page is  http://www.freemail.com
-- Dr.  Papa Sorn, entomology
-- PapaWho@aol.com   for newsgroups
-- PapaWho@Jimsd.e

Dear all,
I'm working on a project to solve a one dimensional, time dependent
Schrodinger's equation with a potential that involves an integral.
     2          /
    d u        |                du 
  K ---    +  L| blah dr   =    --                K and L are complex.
    dr^2       |                dt
               /
I've never solved a PDE numerically.  I was hoping for some good advice
on how to start.  Specifically, I'd like to know what software is out
there that could do something like this.  
c is preferable, c++ is do-able.  I'll do fortran only if learning a new
language would be faster than writing my own c code.
My first reaction was to try to do it on mathematica because I don't know
how to do complex numbers with c, and the results are easily graphable.
However, I hear that MMA is slow.  I also heard that it loses precision (is 
this true??) quickly.
Atny advice, tips or pointers would be greatfully appreciated.  
thanks!
peter

In article <544c8d$4dn@newsbf02.news.aol.com>
yars2@aol.com (YAR S2) writes:
> Is there any way to tap into the power potential of the 231PU atom ?
> If so, how would it / how could it be used as an electromagnetic
> propulsion system for space travel ?
 My guess is yes. That the radioactivity of creation of new matter that
Dirac talked about would be the first science or reasonably close to
the first sciences making use of the fact that the Universe is but One
Atom Everything. Something on the lines of logic that cosmic rays are
new matter sent from the nucleus of 231PU and we may get a science as
to how to steadily generate cosmic rays.
  You see the current beliefs are that cosmic rays with their huge
energies some at 10^19 MeV observed at random in the sky come from some
astro body. I say no, they come from the Nucleus of 231Pu . So you can
see that if we understood this process in detail we may be able to tap
a pipeline into the Nucleus of 231Pu and have these energetic rays
powering Earth. I called Dirac's new radioactivity-- Radioactive
Spontaneous Neutron/Proton/Alpha particle/Beta particle etc
Materialization, or RSNM for short. 
  Use the past history to help guide and when radioactivity was first
discovered it took almost 50 years to put it to use.

Martin Edwards wrote:
> 
> Here is a theory - Binary communication ( accepted as the most elemental
> language) with God ( who is inside all of us, omniprescent).
> 
> Try to understand. Ask yourself a question that leads to the answer Yes or
> No. Listen. Should I abort my unborn child?  The answer is personal and
> correct. Should I drink this?(glass of beer etc) answer is personal and
> correct for the asker of the question, that is all.
> 
> Our god is inside us, we are not god. To ask for guidance and know his or
> her will, leads to : Thy will be done,on earth as it is in heaven.
> 
> The results of ten years effort  implementing this theory can be found at
> 
> http://dove.net.au/~peace/    ---  My little miracle
> 
> It is up to each of us to discover the truth, faith in man is not
> neccesary.
> 
> David K. Davis  wrote in article
> ...
> > Chris Hall (gdc100@york.ac.uk) wrote:
> > : David K. Davis wrote:
> > : >
> > : > Christopher Geggis (cgeggis@jupiter.cs.uml.edu) wrote:
> > : > : On 9 Oct 1996, Ilja Schmelzer wrote:
> > : > :
> > : > : > One property of God is obviously his possibility to work
> miracles. A
> > : > : > God who is not able to work miracles is not very impressing, and
> > : > : > certainly not the Biblical one.
> > : > : >
> > : > : > There is no serious experimental evidence for miracles. Thus, no
> > : > : > experimental evidence for God.
> > : > :
> > : > : As I pointed out earlier, if God does perform a miracle atheists
> will
> > : > : say that its cause is simply unknown or they may even deny its
> existence.
> > : > : They'll demand repeatability just as the debunkers demand
> repeatability
> > : > : with UFOs.  However if God repeatedly caused the miracles the
> atheists
> > : > : would argue that it is some natural cause that we don't yet
> understand.
> > : > : I guess the only way to prove that God exists would be for God to
> > : > : reveal itself to the entire world.  Even then there would be
> doubters.
> > : >
> > : > The whole point of science is to explain the natural world on its own
> > : > terms, without appeal to the supernatural. Were I, personally, to
> meet God
> > : > my first hypothesis would be that I was hallucinating and would start
> > : > trying to recall what I had ingested most recently. I, personally, am
> > : > unwilling to interpret anything I experience as a manifestation of
> God.
> > : > For me, the world is potentially knowable, even when unknown. To say
> God
> > : > did it is simply to say 'I give up'. Were I in heaven I'd want to
> know
> > : > what the angels were made of, who made Him boss, who created Him, why
> He
> > : > isn't a She. And if I didn't want to know, then that's not heaven -
> not
> > : > for me.
> > : >
> > : > -Dave D.
> > :
> > : To say God did it is not necessarily to give up on explanation, it is
> > : sometimes the best or only means of explanation. For example if there
> > : was a book that made systematic and correct predictions of the future
> > : then the best explanation of that would be to say that the book was
> > : written by someone/thing with knowledge of the future, that doesn't
> gove
> > : up on explanation it provides an explanation. [It is of course another
> > : question whether such a book exists, but theoretically it is possible
> to
> > : provide real explanations of things using the supernatural which aren't
> > : just saying 'I give up'.]
> >
> > No. If there were a book that made systematic and correct preditions
> about
> > the future, then the best explanation would be: there a hell of a lot
> > books that make predictions about the future. Some of these books have a
> > terrible record, some a mediocre record, some a good record - this book
> > has an excellent record. I would be expected that a few books were very
> > prescient. But it any case, we are not confronted with such a situation.
> > The Bible, just for example, is certainly not such a book. What it is
> says
> > about the future is very much open to interpretation or very ambiguous or
> > untestable. The Communist Manifesto was much more explicit and got shot
> > down on that account. The God explanation is not a simplifying
> > explanation, but a complicating one. Where did He come from and why did
> he
> > decide to do such and such? It pushes everything beyond the hope and
> reach
> > of explanation.
> >
> > Science doesn't disprove the existence of God - it dispenses with Him.
> > Science is a methodology as is God. Science is endless inquiry. God is
> > the end of inquiry. Meaning not that a religious person can't do science
> > but that at the point where they invoke God they've stopped.
> >
> > -Dave D.
> >
> > - I reply: God is only a concept of the human mind; purely a perception analogous to the perception of our inner self.

Joshua B. Halpern wrote:
> Thus one should speak of mechanical work, which is well defined
> at both the macroscopic and microscopic levels (OK fields can
> do work also) and thermodynmaic work ( or work done by a
> system or on a system) in order to be perfectly precise, but as
> people, we often do not make the distinction in speech or writing
> but rather rely on context to make it clear.  This is not sloppiness,
> but reliance on the knowledge of others
> 
> Regards
> Josh Halpern
Hay Dr. Halpern. My Father says hi.
He's sort of slow at getting around to doing it himself.
Statistically speaking, he works just as hard as I, but in different
ways.
You're supposed to be working, not dilly dallying on the UseNet News.
Smile you're on candid camera.

Michael Zeleny (zeleny@oak.math.ucla.edu) wrote:
: >>>>Of course not.  Anyone familiar with your argumentative style has long
: >>>>abandoned the expectation of seeing you consistently take a principled
: >>>>stand on any position of intellectual consequence
: >>>How cute. Now it would be a sign of integrity to critique science. So 
: >>>far, Russell and co. have mostly been berating me for doing it. Even when 
: >>>I didn't. Why would I?
: >>How cute, indeed.  What I associated integrity with was consistently
: >>taking a principled stand on any position of intellectual consequence.
: >>What you arbitrarily and willfully read into my statement was that the
: >>positions in question were limited to a critique of science.  Thus you
: >>demonstrate the twin trademarks of your rhetorical profession: arguing
: >>at will and without principle or concern for truth on either side of
: >>any issue, and arbitrarily importing your preferred meaning into the
: >>words of your interlocutor.
: >In other words, you made a gratuitous remark without relevance to the 
: >situation. Thanks for clearing that up for us.
: Since you and your tapeworm appear to be in need of clarification, I
: made a remark about your character and comportment of obvious value
: to anyone engaging in a discussion with you, or considering doing so.
Oh that. In that case, you're simply wrong. 
Silke

meron@cars3.uchicago.edu wrote:
: In article <54jlj4$d50@netnews.upenn.edu>, weinecks@mail2.sas.upenn.edu (Silke-Maria  Weineck) writes:
: >meron@cars3.uchicago.edu wrote:
: >: In article <54jbu6$5ag@netnews.upenn.edu>, weinecks@mail2.sas.upenn.edu (Silke-Maria  Weineck) writes:
: >: >meron@cars3.uchicago.edu wrote:
: >: >: In article <54iu77$4mq@uni.library.ucla.edu>, zeleny@oak.math.ucla.edu (Michael Zeleny) writes:
: >: >: >
: >: >: >Thus spake Jacques Derrida:
: >: >: >
: >: >: >	When I take, for example, the structure of certain algebraic
: >: >: >	constructions [ensembles], where is the center? Is the center the
: >: >: >	knowledge of general rules which, after a fashion, allow us to
: >: >: >	understand the interplay of the elements? Or is the center certain
: >: >: >	elements which enjoy a particular privilege within the ensemble?
: >: >: >	...With Einstein, for example, we see the end of a kind of
: >: >: >	privilege of empiric evidence. And in that connection we see a
: >: >: >	constant appear, a constant which is a combination of space-time,
: >: >: >	which does not belong to any of the experimenters who live the
: >: >: >	experience, but which, in a way, dominates the whole construct;
: >: >: >	and this notion of the constant -- is this the center?
: >: >: >
: >: >: >As Sokal rightly says, "Derrida's perceptive reply went to the heart of
: >: >: >classical general relativity:"
: >: >: >
: >: >: >	The Einsteinian constant is not a constant, is not a center. 
: >: >: >
: >: >: >	It is the very concept of variability -- it is, finally, the
: >: >: >	concept of the game. In other words, it is not the concept of
: >: >: >	something -- of a center starting from which an observer could
: >: >: >	master the field -- but the very concept of the game ...
: >: >: >
: >: >: >(Derrida, Jacques. 1970. Structure, sign and play in the discourse of
: >: >: >the human sciences. In The Languages of Criticism and the Sciences of
: >: >: >Man: The Structuralist Controversy, pp. 247-272, edited by Richard
: >: >: >Macksey and Eugenio Donato.  Baltimore: Johns Hopkins Press.)
: >: >: >
: >: >: >A veritable polymath, your frêre Jacques.  I expect the sci.physics
: >: >: >crowd to take special pleasure in this quotation.
: >: >: >
: >: >: You bet.  Best laugh I've had in a long, long time.
: >: >
: >: >I take it you know what Derrida's concept of center is, then? It's a 
: >: >matter of some debate. Please share.
: >: >
: >: I was chuckling at the statement "   ...With Einstein, for example, we 
: >: see the end of a kind of privilege of empiric evidence".  It is quite 
: >: the opposite, in fact.
: >
: >"It is quite the opposite, in fact," meaning what:
: >- we see the beginning of a kind of privilege of empiric evidence?
: >- all kinds of privileges are now accorded to empiric evidence, as 
: >opposed to only certain kinds before?
: >
: The overriding theme of all of 20th century physics is "empirical 
: evidence rules".  To the extent that if empirical evidence seems to 
: contradict our common sense and intuition, then common sense and 
: intuition are to be modified.
In other words, there are no different kinds of empirical evidence? There 
are no different kinds of privilege? Please do explain a bit further just 
what about Hippolyte's statement tickled you so much.
Silke

I have last week joined the U.S. Metric Association, a club of people
who try to get the SI units more widely used in the USA. Membership
costs just $10 for students and $30 for others per year. For this, you
get a bimonthly newsletter "Metric Today" with recent news about for
instance government, education, media and industry activity concerning
U.S. metrification.
In case you also want to join them, just send the cheque and your postal
address to
  U.S. Metric Association
  10245 Andasol Avenue
  Northridge CA 91325-1504
I got my first two issues of the very interesting newsletter within 5
days. A membership application form is also on their home page 
  http://lamar.ColoState.EDU/~hillger/
and for a self-addressed large envelope with 55 cents postage you can
get a sample copy of the newsletter.
Another thing:
I checked yesterday in the Purdue library the ANSI X3.171-1989 standard
that specifies the so-called 3.5" floppy disk. The standard explicitly
says that the original design of this disk format was done entirely in
SI units and that the inch units given in addition to the metric
dimensions in the standard are only provided for the convenience of U.S.
users. The SI units are the authoritive dimensions and the given inch
dimensions should not be converted back to SI units.
The dimension that is closest to 3.5 inch and that gave this disk the
commonly used U.S. nickname is the width of the plastic package. This
dimension is specified as 90.0 mm (3.54 in). Also all other dimensions
in the standard are nicely round millimeter lengths, as I already
guessed from measuring a sample disk.
Markus
-- 
Markus Kuhn, Computer Science grad student, Purdue
University, Indiana, US, email: kuhn@cs.purdue.edu

As I understand it, since Maxwell's eqs indicate that a changing
electric field causes a magnetic field, and conversely, a 
changing magnetic field causes an electric field, if a charge
is accelerating, e.g., going up and down along an antenna,
an observer at some distance away will see both fields
approaching, both intensities sinusoidal, and the ways
perpindicular to each other.  Is an electromagnetic wave any
more than this observation of the fields coming out of
accelerating charges?

In article ,   wrote:
>>
>I'm afraid we're mixing two issues here.  It may be partly my fault 
>since I responded the way I would respond to a fellow physicist, not 
>the way things are phrased in a legal document.  ............... 
Pusillanimous prevarication !
Lew Mammel, Jr.

John Robert Riddell wrote:
> 
> In article <326990FA.5C29@primenet.com>, vanomen  wrote:
> >Superstition?  I call it Faith.  God gave us a free will to decide on
> >our own.  YOu have decided your way and I mine.  2 things to think
> >about though
> >#1 If I am wrong and there is no God?  WEll  worst case I have still
> >tried to live a life and set an example for my family of a way of life
> >that is steps and leaps above the way most people live and treat each
> >other
> >#2 However if I am correct and there is a God(which I am sure there
> >is) then I have eternal Life.
> 
> This a convincing argument.  Are You Hindu? Buddist?  Jew? Perhaps God is one
> of the ancient Gods that are no longer worshipped. What if we worship the
> wrong one? Will we be punished for worshipping the wrong deity? Should we be
> sacrificing babies to the Aztec Gods?
> 
> Please tell me which God you worship, and Why it is safer/better to worship
> him and not one of the others?
Comments from Jerry:
   As far as the individual is concerned all religions provide relief from isolation
in death. The individual goes to the respective Kingdoms of Heaven and is absorbed
by the group.EAch individual thinks he has achieved paradise.He thinks he has
achieved eternal life. The self is lost into the collective. Time ceases to be. Thus
a split second in the world of the dead appears as eternity.The believers of all
faiths happily fade into oblivion.Thus for most, the Kingdom of Heaven is a very
short experience as we view the proocess from the outside.
  NOw, the pit of hell is the same. Thus the evil doers perish faster than they can
even think about it. To them, they are in eternal hell as their clock stops.They are
gone and suffer for only a split second in most cases.
  Choose your religion.If you choose none, then you have no collective to enter. You.
stand alone. Yet, in mercy you will be cast into hell and eliminated instantly.
  Now, if you choose the Arrow of God from Moses to Jesus and choose to follow this
path, then you are eligible to be reborn upon the new Earth as per Isaiah. Then you
will become part of higher man and aneternal life cycle or reincarned births.
  If you believe, then no harm will come to you. And if you don't believe then no
harm will come to you. Yet, the path of life is through belief.It is your choice
and your life. Jerry

In article <54inq9$bdp@ccshst05.cs.uoguelph.ca>, devens@uoguelph.ca (David L Evens) writes:
>Ken Fischer (kfischer@iglou.com) wrote:
>: : In article  
>: : Anthony Potts  writes:
>: : >
>: : >Well, I believe that diamond has a refractive index of around 10, and that
>: : >this is pretty much as high as it gets. This means that light in diamond
>: : >travels at one tenth of its speed in a vacuum.
>
>:        Diamond has a "hardness" of 10.0, but I doubt if
>: the index of refraction is an integer number, hardness is
>: an integer number for diamond because diamond is the
>: hardest material known, and 10 is defined as the upper 
>: limit, with corundum (aluminum dioxide?) being assigned
>: the number 9, and no other natural occurring elements
>: or compositions are above 9.
>
>The refractive index of diamond is almost exactly the same as that of 
>pure water, which is pretty high but nowhere near 10.
>
Not quite.  In the visible range water's refractive index is around 
1.3 while diamond's is somewhere around 2.4-2.5
Mati Meron			| "When you argue with a fool,
meron@cars.uchicago.edu		|  chances are he is doing just the same"

-*------
In article <326D5D1C.78FF@nwu.edu>, brian artese   wrote:
> I have to assume you're familiar ... with linguistics in general ...
   "You keep saying that word.  I do not think it means what
   you think it means."
Modern literary theory is NOT linguistics, indeed, it stands in
considerable tension with linguistics.  Artese's past posts
suggest that he does not know much about linguistics or what goes
on in a linguistics department.  I offer the following
light-hearted table of the the difference (NOT deference) between
linguistics and literary theory, in full cognizance that I know
more about the first than the second.
          Linguistics                 Lit theory
 PURPOSE  General understanding of    Literary and cultural
          language                    criticism
 SAMPLE   "Categorization and naming  "Cyborgs and women"
 TOPIC    in children"                 
 DATA     Empirical research from     'text'
          studies of children 
          learning language to
          in-process PET scans
 FAMOUS   Chomsky, Montagu, Quine,    Derrida, Foucalt, Deleuze,
 NAMES    Saussure                    Saussure
 MATH     Necessary                   Not
 SCIENCE  Is                          Isn't
 STUDIES  Theoretical grammars,       ???
          phonology, semantics, 
          language evolution,
          research methodologies
 CLOSELY  neurology, empirical        women's studies, "soft"
 RELATED  psychology, cognitive       sociology
 FIELDS   science, computer science
As the table indicates, the two disciplines share a common past.
Saussure was a seminal linguist.  But as is the destiny of all
pioneers in a science, his linguistic views have been corrected
by data and superceded by better theories.  Curiously, many of
the Saussurean views that linguistics has since superceded seem
alive and well in literary theory.  
Artese continues:
>  The traditional assumption is that the signifier has *a*
> meaning, a single meaning that grounds it.  But when we 
> answer the question, for instance, "What does 'furious' 
> mean?"  we can only answer by saying something like "it
> means 'angry'" or "it means 'hopping mad'" or "it means 
> 'livid'"  In other words, we never get to a signified, 
> we only get more signifiers.  It turns out that the signifier 
> does not work 'metaphorically' -- that is, as a pointer to 
> some proper meaning that is its 'final foundation' -- it 
> works *associatively*, in relation to other signifiers. ...
It may be that the theory that Artese outlines above remains
useful for literary criticism.  But Artese would be hard pressed
to find a linguist who believes that this is how language
actually works.  Chomsky has pointed out that if children had to
explicitly learn every rule of a natural language's grammar, they
could not learn language, because they are never presented enough
information to do so.  A similar problem applies to Artese's
claim above: there is no way that children could learn the
meaning of words if for each new word they learned they had to
acquire its relationship with all other words.
A related and more fundamental problem with the theory above is
that it fails completely to provide an explanation of meaning at
all.  Meaning is not just a web of words and associations, but is
also tied to our non-linguistic experience.  If Artese wants to
know what "furious" means, he should consider how a young child
would most easily learn this word.  It would not be through a
dictionary (which the child may still be too young to fruitfully
use), but by seeing a furious person and hearing a competent
language user saying "boy is he *furious*".  The child never
needs to explicitly learn the associations of "furious" with
other words; rather, having learned what "furious" means, the
child can figure out these relationships.  (Obviously people *do*
learn new words entirely through their association with other
words, but only *after* they have learned a core vocabulary which
is learned in other fashion.)
-*------
Book recommendation: Stephen Pinker, who heads an MIT cognitive
science center, has written a book that this world has long
needed: a readable account of what linguists now know about
language.  _The_Language_Instinct does a surprisingly good job of
explaining topics from the importance of generative grammars to
the data against which linguists test their theories.  I *highly*
recommend this book.
Russell
-- 
 Newton plain doesn't work, even as an approximation, 
 except within certain limits.        -- Moggin

In article <326C64B3.5A68@dvp.com.au>
Andrew Davison  writes:
> 
> When pulsars were first discovered it was speculated that they were
> signs
> of intellgient life, so your copyright claim is predated by about 25
> years
> or so.
  I have no doubts that very many had the idea slide through their
minds that pulsars are advanced aliens. It is often the case in science
that it is not the first who thought of a idea, but the person who put
it to work.
  If it truly be known who had the first idea of the Atomic Theory, it
may be found that it was not Leucippus, but his mentor. The point is
that Democritus is generally given credit for the Atomic theory because
it put it to work the most.
  Since the first pulsars were discovered, the idea that they are
advanced aliens has been neglected to the tune of neutron stars.
  Here will be my contributions to this field.
 (1) For one there are no neutron stars as currently envisaged. Is
there a creature that is purely DNA? The only ones I can think of are
viruses but I do not think that there is a virus that is 100% DNA or
RNA. I am not sure of that.
  (2) Pulsars that exist naturally are cobalt-nickel all the way up to
heavy element stars.
  (3) Our Asteroid belt may have been a pulsar that blew up
  (4) I have the Atom Totality theory which allows for a spectrum of
different ages in the cosmos. EG. the age of the Thorium Atom Totality,
the Uranium Atom Totality and now our present Plutonium Atom Totality
all living together in the 6 electron space and mass of the 5f6.
  (5) I bring logic to the question can some or most of the  Quasars
and Pulsars be advanced life forms. I have been in the business of
science to long to know that in most cases of science conjecturing if
the idea seems to fit at all with some other ideas, then the idea has a
high probability of being true. And only a fool what not check-it-out. 
My whole entrance into this subject is to check-it-out
  (6) It is the fact that I have the Atom Totality theory that none of
my predeccessors had, that if this thing comes to be true, then I
should get the lionshare, if not all of the credit, except for those
experimenters who first decoded an Alien Message.
  (7) What I am saying is that with the Vantage point of 231PU theory,
that quasars and pulsars in large numbers are Aliens communicating. I
believe this has a stronger chance of being true than false.
  (8) Lastly, I propose to use the EM spectrum to figure out what is
the best forms of communication by aliens should they exist. Once I
figure that out and notice that the EM of pulsars and quasars are often
in agreement with those EM spectrum of likelihood, warrants a strong go
ahead that these are Aliens.
  Has there been a supercomputer attached to every pulsar to keep track
and record of their emmissions and has there been a decoder type
scientist trying to make sense of these EMs?
  THe periodic table, perhaps pulsed backwards because EM like the
Xerox effect gets smaller with each photocopy. Thus if we look at
pulsars as emitting the chemical table backwards..

--- quoting NATURE 10OCT96 ---
SHIFTY GALAXY
   Rawlings et al. report the discovery of a radio source at a redshift
of 4.41, which appears to be an elliptical galaxy viewed early in its
evolution. The optical emissions associated with this radio source
indicate that the host galaxy is neither fully formed nor obviously in
the process of forming stars. Page 502.
--- end quoting NATURE 10OCT96 ---
 Modern current physics and astronomy accept the quasar as a galactic
nucleus and that the immense source of energy is some hypothesized
black hole at its center.
  Of course I say all of this is crap and fakery. GR is fakery. Noone
had the Atom Totality theory when quasars were first discovered. If
they had, they may have put these objects as galaxies in the highly
curved portion of the 5f6 space of 231PU and that the quasar is just a
normal galaxy in a highly curved portion of space. Look at the lobes of
5f6 orbitals and you will notice the high curvature.
  I also need to check-out whether any quasar signal is advanced life.
I believe pulsars have the greater probability, but I do not want to
overlook quasars.
  I need to figure out what EM are the best for long distance
communications. Perhaps quasars are the intergalactic form and pulsars
the interstellar form.

lparker@larry.cc.emory.edu (Lloyd R. Parker) writes...
>Gumby (msw5513@vms1.tamu.edu) wrote:
>: lparker@larry.cc.emory.edu (Lloyd R. Parker) writes...
>: >Patrick T.P. Chin (tchin@dynamo.ecn.purdue.edu) wrote:
>: >: That is not a silly question, ok? 
>: >Asking "How do you explain how a magnetic stirrer works in chemistry?" is 
>: >a silly question.  So would be "How do you explain how cell division 
>: >works in physics?"  or "How do you explain how nuclear fusion works in 
>: >biology?"  or, for that matter, "How do you explain electron orbitals in 
>: >16th century English literature?"
>: I've a friend with a chem degree that works with magnetic stirrers and
>: centrifuges, and other stuff.  Asking how they work is not a stupid
>: question, and the person who operates them should have a clue.
>: The other questions you pose are asking a person with no contact with
>: with those concepts about them.  That is not the same as asking a
>: "chemist", when many chemists have exposure to magnetic stirrers, about
>: magnetic stirrers.
>Sure it is.  If not for nuclear fusion, there'd be no elements heavier 
>than hydrogen or helium, and no life, so you could argue just as much 
>that a biologist should know how that works as a chemist should know how 
>a stirrer works.  
But a biologist doesn't work with fusion.  A chemist works with a stirrer.
>But perhaps this will be even clearer:  Biologists also work with
>stirrers, spectrometers, etc.  So should they also know as much about them
>as a physicist or an engineer?  Does an English teacher need to know
>exactly how a modern printing press works?  Or how paper is made?  Or why 
>the graphite in a pencil works the way it does?  They certainly work with 
>these. 
Yes.  I'm a theater major, and I can tell you how the shear forces of the
paper fibers erode the graphite, resulting in a black residue.  I have a
rough idea of the difference in composition between a #2 pencil I use to
write plays with and the 2H lead I use for drafting.  I can go to the EE
department and buy a bunch of AND and OR gates and make a crude, but
working, model of the CPU in the computer I'm typing on.  I've been in a
newspaper printing building and seen exactly how a modern press works.
I'm interested in all the aspects of what afects my life.  I can tear
down and rebuild the engine in my car.  I can do the same with my
bicycle and motorcycle.
Why is it you can't even explain how a centrufuge works, since you don't
know what torque is?  You are the reason I want to become a teacher,
because of all the substandard, unknowledgable teachers out there.
Marc

In article <54julh$k2p@netnews.upenn.edu>, weinecks@mail1.sas.upenn.edu (Silke-Maria  Weineck) writes:
>
>meron@cars3.uchicago.edu wrote:
>: In article <54jlj4$d50@netnews.upenn.edu>, weinecks@mail2.sas.upenn.edu (Silke-Maria  Weineck) writes:
>: >meron@cars3.uchicago.edu wrote:
>: >: In article <54jbu6$5ag@netnews.upenn.edu>, weinecks@mail2.sas.upenn.edu (Silke-Maria  Weineck) writes:
>: >: >meron@cars3.uchicago.edu wrote:
>: >: >: In article <54iu77$4mq@uni.library.ucla.edu>, zeleny@oak.math.ucla.edu (Michael Zeleny) writes:
>: >: >: >
>: >: >: >Thus spake Jacques Derrida:
>: >: >: >
>: >: >: >	When I take, for example, the structure of certain algebraic
>: >: >: >	constructions [ensembles], where is the center? Is the center the
>: >: >: >	knowledge of general rules which, after a fashion, allow us to
>: >: >: >	understand the interplay of the elements? Or is the center certain
>: >: >: >	elements which enjoy a particular privilege within the ensemble?
>: >: >: >	...With Einstein, for example, we see the end of a kind of
>: >: >: >	privilege of empiric evidence. And in that connection we see a
>: >: >: >	constant appear, a constant which is a combination of space-time,
>: >: >: >	which does not belong to any of the experimenters who live the
>: >: >: >	experience, but which, in a way, dominates the whole construct;
>: >: >: >	and this notion of the constant -- is this the center?
>: >: >: >
>: >: >: >As Sokal rightly says, "Derrida's perceptive reply went to the heart of
>: >: >: >classical general relativity:"
>: >: >: >
>: >: >: >	The Einsteinian constant is not a constant, is not a center. 
>: >: >: >
>: >: >: >	It is the very concept of variability -- it is, finally, the
>: >: >: >	concept of the game. In other words, it is not the concept of
>: >: >: >	something -- of a center starting from which an observer could
>: >: >: >	master the field -- but the very concept of the game ...
>: >: >: >
>: >: >: >(Derrida, Jacques. 1970. Structure, sign and play in the discourse of
>: >: >: >the human sciences. In The Languages of Criticism and the Sciences of
>: >: >: >Man: The Structuralist Controversy, pp. 247-272, edited by Richard
>: >: >: >Macksey and Eugenio Donato.  Baltimore: Johns Hopkins Press.)
>: >: >: >
>: >: >: >A veritable polymath, your frêre Jacques.  I expect the sci.physics
>: >: >: >crowd to take special pleasure in this quotation.
>: >: >: >
>: >: >: You bet.  Best laugh I've had in a long, long time.
>: >: >
>: >: >I take it you know what Derrida's concept of center is, then? It's a 
>: >: >matter of some debate. Please share.
>: >: >
>: >: I was chuckling at the statement "   ...With Einstein, for example, we 
>: >: see the end of a kind of privilege of empiric evidence".  It is quite 
>: >: the opposite, in fact.
>: >
>: >"It is quite the opposite, in fact," meaning what:
>: >- we see the beginning of a kind of privilege of empiric evidence?
>: >- all kinds of privileges are now accorded to empiric evidence, as 
>: >opposed to only certain kinds before?
>: >
>: The overriding theme of all of 20th century physics is "empirical 
>: evidence rules".  To the extent that if empirical evidence seems to 
>: contradict our common sense and intuition, then common sense and 
>: intuition are to be modified.
>
>In other words, there are no different kinds of empirical evidence? There 
>are no different kinds of privilege? Please do explain a bit further just 
>what about Hippolyte's statement tickled you so much.
>
Hippolyte?  And who's this Hippolyte?  Anyway, you ask lots of 
questions.  Why won't you start with explaining what does Derrida mean 
by "constant" and "center".  In other words, assume that I'm 
completely ignorant of the language he uses (a reasonable assumption) 
and translate the passage above to common speak.  While we're at this, 
could you also explain in what sense do you use the word "privilege" 
when referring to empirical evidence.
Mati Meron			| "When you argue with a fool,
meron@cars.uchicago.edu		|  chances are he is doing just the same"

In article <54juf0$hn3@ssbunews.ih.lucent.com>, lew@ihgp167e.ih.att.com (-Mammel,L.H.) writes:
>In article ,   wrote:
>>>
>>I'm afraid we're mixing two issues here.  It may be partly my fault 
>>since I responded the way I would respond to a fellow physicist, not 
>>the way things are phrased in a legal document.  ............... 
>
>
>Pusillanimous prevarication !
>
You forgot the smiley.
Mati Meron			| "When you argue with a fool,
meron@cars.uchicago.edu		|  chances are he is doing just the same"

Hello fellow scientists..
I would like to pose a question which I have been researching for many years and have
never got an answer.  I would like to know whether there is any material or substance
which would shield the magnetic attraction of a magnet, ie. to stop the magnetic field
going through.
Hope someone can help me out with an solution!
Regards,
Alfio  

greyhawk wrote:
> 
> Juan Carlos Barroux R. - SunService  wrote in
> article <5443il$7gs@jethro.Corp.Sun.COM>...
> > In article pijOy8PfQ7Se088yn@nyx.net, agambino@nyx.net (Anthony S.
> Gambino) writes:
> > >
> > > Well, a dino fossil wouldn't have an intact intestinal system.  But
> > > finding a homo sapiens sapiens skull punctured by a T. Rex tooth
> > > (intact), and having the forensic evidence match up conclusively,
> > > for instance, would be a quite valid criterion for falsification of
> > > much of the ToE...
> >
> >   Well, not exactly.
> >
> >   There is at least another possibility: Time travel.
> >
> 
> A H. sapiens skull with T. Rex tooth(intact)?  I'd be more inclined to
> agree with j.c., definitely time travel.  By the way, who on Earth
> decided to add rec.arts.poems to this senseless debate?
(rec.arts groups removed)
There's always the possibility that a fossil tooth could have been used
as a murder weapon by another H.S.
Spear marks / cutting marks on T.Rex bones would be more conclusive.
Barry. 
-- 
E-mail: Barry_Vaughan@hp.com
------------------------------------------------------------------------
...so the Crocodile said "If you say truely what I will do, then I will
release your child, if not, I shall devour it."
And the mother answered... 
------------------------------------------------------------------------
My opinions do not necessarily reflect those of Hewlett-Packard Ltd.

In article <540p0h$2r9@news.bu.edu>, mbk@bu.edu (Mark B. Kraft) wrote:
> >mbk@bu.edu (Mark B. Kraft):
> >| So, when someone says to you, "X is wrong," you think something along
> >| the lines of: There exists a Y in the same domain which we posit to be
> >| not wrong.  ...
> 
> >That's very Aristotelian of you.  No, the first thing I
> >would think of would be the social, especially the
> >linguistic, context of the statement.
> 
> But wouldn't this imply not only that calling something wrong could
> mean a variety of things, depending on the context, but that the
> speaker and the listener could attach different meanings to it
> depending on their interpretations of the context? Wouldn't that all be
> terribly imprecise and problematic?
> 
> ============================================
>               M.B.Kraft, PhD
> Any opinions I express are, at most, my own.
> ============================================
ok ok i admit it i'm ignorant ,but 2 me at least i think the " problem"
you see in this arguement isn't really a problem at all the further
undiffernaiting of things such as this is what drives poststructualism
it's only a logical problem in other words.
bye

Isaac Brownell  wrote:
>Perhaps someone out there can help me with a question...
>
>What is the limmiting factor on MRI resolution?  The context of this question 
>is another question: Why can't we make a high power, high frequency field 
>using a really small magnetic coil and get imaging powers great enough to 
>view cellular ultrastucture?  Is this possible and just not being done?  I'm 
>assumeing that the proton concentration difference between membrane bound 
>organelle and the cytoplasm is sufficient to be imaged.
>
>Please e-mail responces as I don't frequently check these news groups.  
>Thanks!
One limit to imaging resolution is the wavelength of the exciting 
radiation.  Another is the insensitivity of NMR - at 60 MHz you get a 
population inversion excess of about 8 protons/million (kT is a pisser). 
 300 MHz is better, but by less than a factor of 10.  If you are going to 
FT listen for the FID, you will not be 100% efficient in your detection 
of photons, and Brownian motion will eat you between pulses.
You are not going to get much beyond 600 MHz unless you invent new magnet 
technology.  Remember, the field not only must be intense, it must be 
incredibly uniform.
-- 
Alan "Uncle Al" Schwartz
UncleAl0@ix.netcom.com ("zero" before @)
http://www.netprophet.co.nz/uncleal/        (best of + new)
http://www.ultra.net.au/~wisby/uncleal.htm  (lots of + new)
 (Toxic URLs! Unsafe for children, Democrats, and most mammals)
"Quis custodiet ipsos custodes?"  The Net!

In <54jd0v$7pk@dfw-ixnews7.ix.netcom.com> odessey2@ix.netcom.com(Allen
Meisner) writes: 
>
>In <54itja$ckd@dfw-ixnews11.ix.netcom.com> Alan \"Uncle Al\" Schwartz
> writes: 
>>
>>odessey2@ix.netcom.com(Allen Meisner) wrote:
>>>    Since we know the energy equivalence of the elementary
particles'
>>>rest mass and since we know the dimensions of the elementary
>particles,
>>>shouldn't we also be able to calculate the spacetime curvature of
the
>>>particles themselves, as opposed to the spacetime curvature it
>produces
>>>in the surrounding spacetime?
>>>
>>>Edward Meisner
>>
>>The "dimensions" of elementary particles?  The best we can do for
>nice, 
>>fat, cold, stable atoms is 90% probability thermal ellipsoids.  Have
>you 
>>ever heard of a guy named de Broglie?
>>
>>-- 
>>Alan "Uncle Al" Schwartz
>>UncleAl0@ix.netcom.com ("zero" before @)
>>http://www.netprophet.co.nz/uncleal/        (best of + new)
>>http://www.ultra.net.au/~wisby/uncleal.htm  (lots of + new)
>> (Toxic URLs! Unsafe for children, Democrats, and most mammals)
>>"Quis custodiet ipsos custodes?"  The Net!
>>
>>
>    But we do know the dimensions of the nucleus, don't we? If this is
>so, it shouldn't be such a great step to apply general relativity. I
am
>not sure how the equation would look, but you would probably not need
>the gravitational constant, since you are treating the mass in terms
of
>its energy equivalent. Since the Tensor in general relativity refers
to
>the energy distribution, why couldn't we just substitute the
appropiate
>values into the equation? Or you could use the equations that Jason
>Blood used, in the "finding the curvature for given QM field" posting.
>He used equations to find the curvature of a massless boson. Couldn't
>this equation be used? It might give interesting results.
>
>Edward Meisner
    Could you explain to me de Broglie's equations? Would it be
possible to substitute the spacetime curvatures of the electron and
proton into de Broglie's equations? The expression of these particles
in terms of spacetime might be fruitful and might give both
explanations for phenomena that are not clearly understood at present
as well as interesting predictions.
Edward Meisner

meron@cars3.uchicago.edu wrote:
: In article <54julh$k2p@netnews.upenn.edu>, weinecks@mail1.sas.upenn.edu (Silke-Maria  Weineck) writes:
: >
: >meron@cars3.uchicago.edu wrote:
: >: In article <54jlj4$d50@netnews.upenn.edu>, weinecks@mail2.sas.upenn.edu (Silke-Maria  Weineck) writes:
: >: >meron@cars3.uchicago.edu wrote:
: >: >: In article <54jbu6$5ag@netnews.upenn.edu>, weinecks@mail2.sas.upenn.edu (Silke-Maria  Weineck) writes:
: >: >: >meron@cars3.uchicago.edu wrote:
: >: >: >: In article <54iu77$4mq@uni.library.ucla.edu>, zeleny@oak.math.ucla.edu (Michael Zeleny) writes:
: >: >: >: >
: >: >: >: >Thus spake Jacques Derrida:
: >: >: >: >
: >: >: >: >	When I take, for example, the structure of certain algebraic
: >: >: >: >	constructions [ensembles], where is the center? Is the center the
: >: >: >: >	knowledge of general rules which, after a fashion, allow us to
: >: >: >: >	understand the interplay of the elements? Or is the center certain
: >: >: >: >	elements which enjoy a particular privilege within the ensemble?
: >: >: >: >	...With Einstein, for example, we see the end of a kind of
: >: >: >: >	privilege of empiric evidence. And in that connection we see a
: >: >: >: >	constant appear, a constant which is a combination of space-time,
: >: >: >: >	which does not belong to any of the experimenters who live the
: >: >: >: >	experience, but which, in a way, dominates the whole construct;
: >: >: >: >	and this notion of the constant -- is this the center?
: >: >: >: >
: >: >: >: >As Sokal rightly says, "Derrida's perceptive reply went to the heart of
: >: >: >: >classical general relativity:"
: >: >: >: >
: >: >: >: >	The Einsteinian constant is not a constant, is not a center. 
: >: >: >: >
: >: >: >: >	It is the very concept of variability -- it is, finally, the
: >: >: >: >	concept of the game. In other words, it is not the concept of
: >: >: >: >	something -- of a center starting from which an observer could
: >: >: >: >	master the field -- but the very concept of the game ...
: >: >: >: >
: >: >: >: >(Derrida, Jacques. 1970. Structure, sign and play in the discourse of
: >: >: >: >the human sciences. In The Languages of Criticism and the Sciences of
: >: >: >: >Man: The Structuralist Controversy, pp. 247-272, edited by Richard
: >: >: >: >Macksey and Eugenio Donato.  Baltimore: Johns Hopkins Press.)
: >: >: >: >
: >: >: >: >A veritable polymath, your frêre Jacques.  I expect the sci.physics
: >: >: >: >crowd to take special pleasure in this quotation.
: >: >: >: >
: >: >: >: You bet.  Best laugh I've had in a long, long time.
: >: >: >
: >: >: >I take it you know what Derrida's concept of center is, then? It's a 
: >: >: >matter of some debate. Please share.
: >: >: >
: >: >: I was chuckling at the statement "   ...With Einstein, for example, we 
: >: >: see the end of a kind of privilege of empiric evidence".  It is quite 
: >: >: the opposite, in fact.
: >: >
: >: >"It is quite the opposite, in fact," meaning what:
: >: >- we see the beginning of a kind of privilege of empiric evidence?
: >: >- all kinds of privileges are now accorded to empiric evidence, as 
: >: >opposed to only certain kinds before?
: >: >
: >: The overriding theme of all of 20th century physics is "empirical 
: >: evidence rules".  To the extent that if empirical evidence seems to 
: >: contradict our common sense and intuition, then common sense and 
: >: intuition are to be modified.
: >
: >In other words, there are no different kinds of empirical evidence? There 
: >are no different kinds of privilege? Please do explain a bit further just 
: >what about Hippolyte's statement tickled you so much.
: >
: Hippolyte?  And who's this Hippolyte?  
The quote that amused you is from Jean Hippolyte, French philosopher. 
He is asking a question, during a conference at Johns Hopkins 
University in the 60s, after Derrida's talk on "Structure, Sign, and 
Play." Zeleny was quoting, I assume, from "The Structuralist 
Controversy," that collects papers from the conference as well as 
transcriptions of the discussion section. The second quote (the one 
about "center") is part of Derrida's oral reply. 
: Anyway, you ask lots of A
: questions.  Why won't you start with explaining what does Derrida mean 
: by "constant" and "center".  In other words, assume that I'm 
: completely ignorant of the language he uses (a reasonable assumption) 
: and translate the passage above to common speak.  While we're at this, 
: could you also explain in what sense do you use the word "privilege" 
: when referring to empirical evidence.
I don't know what Hippolyte meant by "kind of privilege" -- he's asking a 
tentative question, not publishing an article. I would have liked to ask 
him. Since I can't, I assume, since I know him to be an intelligent 
thinker, that he had something specific in mind; probably something 
rather simple, and he might have agreed that he worded it unfortunately. 
I don't know, I'm speculating. 
	I don't have "TSC" at hand, I'm not in my office right now. As 
far as I remember (and keep in mind that I'm writing off the top of my 
head), the question is a metaphysical one, not a technical/scientific 
one. Nobody is doubting here (as some t.o. folks assumed a few months 
back) that the speed of light isn't constant. The question is rather 
whether this constancy provides a center in the sense of a grounding. 
Derrida seems to suggest (and that's off the top of _his_ head, remember 
he's not giving a talk about physics here, neither is he publishing his 
thoughts on physics) that SR does not provide that kind of stability that 
would render Derrida's thoughts on structure in philosophy nil.
"Structure, Sign, and Play" is a rather short essay. If you have trouble 
finding it in your library, I'd be happy to snailmail you a xerox copy. 
It should provide the context we'd need here to establish whether 
Hippolyte and Derrida are really as ridiculous as you seem too ready to 
assume. 
Silke

candy@mildred.ph.utexas.edu (Jeff Candy) wrote:
>
>Alan "Uncle Al" Schwartz:
>
>|> > Now, if we were to  put a couple of RF quartz crystals (or whatever) in
>|> > proximity in a plasma and excite a pleasant organ pipe resonance at a
>|> > sufficiently high frequency,
>|> > 
>|> >   1) could we get the enough density differentiation between nodes and
>|> > antinodes to make a stack of optical, UV, or higher frequency etalons?
>
>Marcus H. Mendenhall:
> 
>|> I think here you will run into trouble.  The collision length for the
>|> ions in a plasma of usual densities (<<1 atm) is typically long enough
>|> that I would not expect it to nicely support acoustic waves at optical
>|> wavelengths.  You would certainly be in a very complex regime to
>|> understand, at the very least.  
>
>For densities on the order of 10^10 /cm^3, the plasma has collision 
>frequencies of roughly 10^(-5)/s (ee) and 10^(-4)/s (ei).  Thus, 
>it is essentially collisionless.  A well-known result for the 
>collisionless theory of these waves is that they are *heavily* 
>ion Landau-damped unless T_e >> T_i.  
>
>The latter condition is the constraint required for propagating 
>ion-acoustic waves.  In any case, taking c_s about 10^5 cm/s (my last 
>calculation -- much slower than the electron thermal speed) and 
>omega = 1MHz, gives 
>
>        k = omega/c_s = (10^6 /s) / (10^5 cm/s) = 10 /cm .
>
>The wavelength of a 1MHz acoustic mode in a T_e = 1eV >> T_i plasma 
>would be about 1mm -- the high end of the microwave region.
>
>I'm still not quite sure exactly what you want the plasma to do.
One millimeter won't do it.  I was hoping for alternating transparent and 
reflecting walls on the order of a few nanometers.
The Casimir effect varies as the inverse fourth power of an etalon gap,  
The smallest physical construct of "Casimatter," matter partially 
excluding quantum zero point fluctuations, would be about 70nm of Al 
alternating with 35 nm of MgF2 (half-wave of about 80 nm).  At shorter 
wavelengths Al becomes transparent and no heavier metal is reflective.  
The bulk effect is still about 5 orders of magnitude too small to detect 
as a change in gravitational and inertial mass.
A plasma has the pleasant property of strongly interacting with 
electromagnetic radiation.  I was hoping to fabricate a dynamic 
Casimatter stack.  Ah well...
-- 
Alan "Uncle Al" Schwartz
UncleAl0@ix.netcom.com ("zero" before @)
http://www.netprophet.co.nz/uncleal/        (best of + new)
http://www.ultra.net.au/~wisby/uncleal.htm  (lots of + new)
 (Toxic URLs! Unsafe for children, Democrats, and most mammals)
"Quis custodiet ipsos custodes?"  The Net!

In article <54k1o7$cgr@peaches.cs.utexas.edu>, turpin@cs.utexas.edu
(Russell Turpin) wrote:
> -*------
> In article <326D5D1C.78FF@nwu.edu>, brian artese   wrote:
> > I have to assume you're familiar ... with linguistics in general ...
> 
>    "You keep saying that word.  I do not think it means what
>    you think it means."
> 
> Modern literary theory is NOT linguistics, indeed, it stands in
> considerable tension with linguistics.  Artese's past posts
> suggest that he does not know much about linguistics or what goes
> on in a linguistics department.  I offer the following
> light-hearted table of the the difference (NOT deference) between
> linguistics and literary theory, in full cognizance that I know
> more about the first than the second.
> 
> 
>           Linguistics                 Lit theory
> 
>  PURPOSE  General understanding of    Literary and cultural
>           language                    criticism
> 
>  SAMPLE   "Categorization and naming  "Cyborgs and women"
>  TOPIC    in children"                 
> 
>  DATA     Empirical research from     'text'
>           studies of children 
>           learning language to
>           in-process PET scans
> 
>  FAMOUS   Chomsky, Montagu, Quine,    Derrida, Foucalt, Deleuze,
>  NAMES    Saussure                    Saussure
> 
>  MATH     Necessary                   Not
> 
>  SCIENCE  Is                          Isn't
> 
>  STUDIES  Theoretical grammars,       ???
>           phonology, semantics, 
>           language evolution,
>           research methodologies
> 
>  CLOSELY  neurology, empirical        women's studies, "soft"
>  RELATED  psychology, cognitive       sociology
>  FIELDS   science, computer science
> 
> As the table indicates, the two disciplines share a common past.
> Saussure was a seminal linguist.  But as is the destiny of all
> pioneers in a science, his linguistic views have been corrected
> by data and superceded by better theories.  Curiously, many of
> the Saussurean views that linguistics has since superceded seem
> alive and well in literary theory.  
> 
Nice table, but a little incomplete.  There are places where the two
disciplines can and do intersect -- my own field, classics, is one.  I
think it would fit nicely in both columns.
-- 
SPBurris at Cornell University
Greek, Latin and bagpipes!

In <326C9C7E.167EB0E7@smug.student.adelaide.edu.au> Fish
 writes: 
>
>William Sommerwerck wrote:
>> Tony wrote:
>> > from fish. Our evolution in the water caused us to develop eyes
that
>> > didn't see water (i.e., that perceived it as transparent). There
is
>> > otherwise nothing inherently "clear" about water; the H20 molecule
>> > emits photons when light is shed upon it, just like every other
type
>> > of matter in the universe. Why can't we "see" water (i.e., why do
we
>> > see right through it)? Things didn't HAVE to be this way.
>> 
>> In "large" quantities, water IS visible.
>
True, but irrelevant.   We only needed to see through the water
immediately surrounding us, within a radius of around 10 meters or so,
to give us enough time to avoid predators and search for food.  
Besides, you miss my original point.   I never meant to say that water
in ANY form, or in ANY quantity, was invisible.    Icebergs aren't
clear.   Fog is water but one cannot see through it when it's dense.  
Our eyes only had to evolve in adaptation to their immediate
surroundings, where vision was crucial to survival of the species.  All
those who bring up other substances which are "clear" -- air, hydrogen
peroxide, methyl alcohol, etc. are missing the point entirely.   
I maintain:   Water is clear because we evolved from fish.   
Tony

+@+.+ (G*rd*n) wrote:
>Silke-Maria  Weineck  wrote:
>| >: > ... I'm sure Mati is much less fazed by this than you seem
>| >: > to be, for reasons still obscure. 
>Russell Turpin (turpin@cs.utexas.edu):
>| >: Silke, I am not phased by it at all.  It is not a thread that
>| >: I have that much interest in following.  Really. [...]
>moggin@bessel.nando.net (moggin):
>| 	This is really Meg's job, but I'll lend a hand.  Silke
>| is right:  the spelling is "fazed."  (Unless of course Russell
>| is alluding to the standard side-arm of the Enterprise crew.)
>I've seen and heard "faced", as well.  
Only with too much to drink and then only as part of a compound
modifier.
Ken

rparson@spot.Colorado.EDU (Robert Parson) writes:
}
}>mention "torque" at all, it is simply to show the conservation of angular
}>momentum principle for the classical system.  Then they go on to the
}>quantum system where "torque" seems to play no part whatsoever. 
}
} The word "torque" appears less frequently in the quantum theory than
} in the classical, for the same reason that "force" appears less
} frequently in quantum theory. The Hamiltonian and the canonical momenta
} move to the foreground, and forces and torques become secondary
} quantities. Nevertheless the concept is still there - through the
} Ehrenfest and Hellman-Feynman theorems. 
They are also implicit in the statements about the Hamiltonian 
that lead to L being a good quantum number, for example.  From 
my observations of chemistry graduate students in a nuclear 
chemistry program that required they take the physics QM course 
in addition to the chemistry QM course, the chem students suffered 
from a lack of experience with the classical Hamiltonian.  They 
seemed to see QM as a set of rules, not a simple extension of 
classical mechanics via the bracket formalism.  They were less 
prepared for grad QM than a 1st year physics major despite having 
taken a year of grad QM -- but no mechanics -- in chemistry. 
}> And, this
}>is just on the dynamics side of chemistry -- if you go over to the
}>electronic structure side, which is all quantum stuff, I am even more
}>certain that "torque" is never mentioned. 
}
} That is because electronic structure theory deals largely (though
} not entirely) with time independent properties. 
Which is only possible if dL/dt = 0, that is, no external torques. 
-- 
 James A. Carr        |  Raw data, like raw sewage, needs 
    http://www.scri.fsu.edu/~jac        |  some processing before it can be
 Supercomputer Computations Res. Inst.  |  spread around.  The opposite is
 Florida State, Tallahassee FL 32306    |  true of theories.  -- JAC

turpin@cs.utexas.edu (Russell Turpin) wrote:
>I think it would be more fun, and perhaps as relevant, to treat
>physics and Christianity as sets of books, and compare how these
>books are treated.  Let's see ... one set is full of math, are
>typically quite expensive, and are used primarily as objects of
>study and then souvenirs from one's student days.  They are
>rarely stored on the same shelf as dictionaries.  The other
>almost never has math, and some of its books are given away by
>preachers and in hotels, and they are used primarily to hold up
>dictionaries.  ('Fess up: isn't your Bible on the same shelf as
>your dictionary?)  This just a start, and it could get quite fun
Bibles?  Hmm, let's see.  The Gutenberg Bible produced in Mainz,
Germany last sold at auction for $4,900,000, a tad more than your math
text.  Crummy old run of the mill bibles like the Whitechurch sixth
edition sell for $2800; the Douai New Testament for $1000; Tyndale's
version for $5300; and so on.  You better put those bibles up in your
glass case in the big house, boy.
Ken