Newsgroup sci.physics 215536

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In article ,
Walter Polkosnik  wrote:
> On Wed, 8 Jan 1997, J. D. McDonald wrote:
> 
> > Walter Polkosnik wrote:
> > > 
> > > Is there a quick and simple technique for measuring the coherence
length of
> > > a laser? I know of the Michelson interferometer technique, I'd like
> > > to get a detailed description of that technique or another. If anyone
could
> > > provide me with a reference to a text, paper or even web page, I'd
> > > appreciate it.
> > 
> > 
> > Interferometers are suitable if the coherence length is short,
> > a couple of meters or less. If it is longer than a foot or two,
> > then you can use electronic techniques: you shine it on
> > a fast enough detector diode, then digitize and fourier
> > transform the resulting signal. This latter method certainly
> > is quicker and simpler.
> > 
> > Doug McDonald
> 
> I am guessing that the speed of the diode needed is of the order of the
> inverse coherence time of the laser (practially it can't be the frequency
> of the laser)? Do you know of a reference to the details of this technique?
> Unfortunatelty it doesn't sound affordable on my budget.
Hmmm, I don't know about the idea above, but there's a similar method where
a signal is split, one arm is delayed longer than the coherence time, and
then the signals are recombined (fiber works great for this). The resulting
signal has a lorentzian lineshape (viewable on your spectrum analyser)
twice the actual width of the laser spectrum (if the delay is several times
the coherence time, and the laser has a lorentzian lineshape). The
linewidth is the inverse of the coherence time is the coherence length over
c. To avoid 1/f noise an acousto optic modulator is used to frequency shift
one arm so the desired signal appears at higher frequency. The most handy
reference I have on the concept is a paper about what kind of shapes you
get if your delay is not several times the coherence length, but I guess
you could work backwards from that.
\bibitem{McGrath} L.\ E.\ Richter, H.\ I.\ Mandelberg, M.\ S.\ Kruger,
and P.\ A.\ McGrath, `` Linewidth determination from self-heterodyne
measurements with subcoherence delay times,'' IEEE J. Quantum Electron.
{\bf QE-22},  2070 (1986).
-- 
C. Geoffrey Fanning
fanning@leland.stanford.edu
http://www-leland.stanford.edu/~fanning/

On Sun, 12 Jan 1997 15:13:08 GMT, Ken Fischer wrote:
: 
:         Another frustration I have, is that everybody
: on the surface of the Earth are accelerated at 1 g
: constantly, but they don't know it. :-)
: 
You are correct in saying the everyone on the surface is _constantly_ 
accelerating, but not at 1g.  The constant acceleration arises due to the
rotation of the Earth about it's axis and is equal to approx. 
0.034 m/(s^2) or 0.34% of g.
If I were falling freely, I would accelerate at 1g toward the ground due
to the gravitational attraction b/w myself and the Earth.  But right now
the chair on which I'm sitting is preventing me from falling.
-- 
+-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+-=-=-=-=-=-=-=-=-=-=-=-=-+
| Trevor Robert Fulton                | fulton@skatter.usask.ca | 
| Saskatchewan Accelerator Laboratory | Phone:   (306) 966-8520 |
| Saskatoon, Sask.                    | Fax:     (306) 966-6058 |
+-------------------------------------+-------------------------+
| "A chicken is just an egg's way of making more eggs."         |
|   -- John Gribbin --                                          |
+-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
The opinions I've expressed are mine alone.
-=-

In <32D5FE70.18D3@de.att.com> Norbert Kolvenbach  wrote:
>Joseph H Allen wrote:
>> 
>> In article <01bbfdcb$f741e5a0$LocalHost@brian>,
>> Brian Tozer.  wrote:
>> 
>> >> >> Here are some paradoxes: Now the negation of "all ravens are black" 
is
>> >> >> "all non-black things aren't ravens".  The two statements are
>> >> >> logically equivalent.
>> Now the statement "all non-black things aren't ravens" is logically
>> equivalent to "all ravens are black".  Thus all of the non-black things 
you
>> find which aren't ravens (your red coat, the white ceiling, etc.) also
>> support your generalization that "all ravens are black".
>From "all non-black things aren't ravens" it follows, that "all ravens are 
>black". But the reverse is NOT true, hence no equivalence!
Yes it is. IF all ravens are black (no painted or albino ravens), then all 
non-black things are not ravens.
I have no trouble with each non-black thing I see - my computer but not my 
printer, my hands but not my fax - adding to the stock of non-black things 
that help to confirm the statement that all ravens are black. But you have to 
admit that every black raven adds relatively substantially to the stock of 
ravens, compared to the infinitessimal amount that every non-black non-raven 
adds to the stock of non-ravens. Almost everything in the universe isn't a 
raven.
This is what Bertrand Russell called a veridical paradox. Strange but true.
I have a problem with the equivalence though: A single non-black raven 
DISproves the statement (or its equivalent), but neither non-black non-ravens 
(like almost everything), black non-ravens (like my printer and fax), nor 
black ravens (of course) will DISprove it or the equivalent. So are the 
statements really equivalent? 
--
Hugh Young, Pukerua Bay, Nuclear-free Aotearoa / NEW ZEALAND 
            Ivory Soap - 0.7 grams of IMPURITIES in every 125 gram bar!

Jay A. St. Pierre wrote:
> 
> I came across the following explanation at
> http://www.imponderables.com/new1.html on Jan. 12, 1997.  It purports to
> explain why fans (ceiling fans in particular) get so dusty.  I am
> wondering if the explanation is complete.  It seems to me that static
> electricity is insufficient to explain why the dust can continue to stay
> on the fan; I thought this had to due with fluid dynamics, in particular
> that the air flow near the surface of the fan can be quite low even
> though the fan may be generating quite a strong breeze.
> 
> Please e-mail replies.  Thanks.
> 
> -Jay
> 
> ----------
> 
 snipped article
Hi Jay,
Seems I've seen a lot of dust on unpainted metal fan blades and squirrel
cage rotors. If the blades were grounded, then electrostatic attraction
would be ruled out as the *only* cause for dust accumulation.
In addition to dust in the air I'll bet there are cooking oil vapors
etc. which could deposit on the blades and glue the dust in place.
Even though the blades may have small area compared to other dust
collecting devices, like CRT screens and knick-knacks, the motion of the
blades sweep out larger areas over time. Some mean free path calcultions
are in order.
This sounds like a good science fair project or PHD thesis topic(%>)
Regards,
John

Alex Vange  writes:
> David Kastrup  wrote:
> >Pretty much unthinkable in most civilized states with a separation of
> >religion and state.  Now of course I am aware that the Jewish canon of
> >law which is supposedly valid for Christians as well contains *very*
> >strict outruling of homosexuality.  But it contains a host of other
> >rules with equally strict penalties which nobody cares a bit about any
> >more.  We don't lock women away for the time of their period, for
> >example.  No gynaecologist and his patients get sentenced to death
> >because they uncovered the "blood flow" of the woman.
> >
> >But Christians have always been very selective in what laws they want
> >to be zealots about, and the American are traditionally pretty zealous.
> >
>     No, the death penalty is only for serious crimes such as homosexual 
> perversion.
Well, uncovering the nakedness of a woman in the time of her
uncleanness is mentioned in Lev 18:19, among with homosexuality (Lev
18:22) and sodomy (intercourse with animals) Lev 18:23.
Sounds like being pretty much in the same vein to me.
> There is some mention of uncleanness regarding menstruating, 
> but that is about it. A great nation would outlaw homosexual perversion 
> and promote a good culture for quality people to live in.
Don't forget that the origin of Western civilization is Greek, and
that in particular the finer points of "love" later taken up into the
amour courtois concepts of the middle ages were developed with regard
to relationships between men and boys.  The Greek were certainly the
most civilized Western people of their time.  Which need not mean much...
> And the Old 
> Testament is not Jewish canon.
Then presumably Moses was not a jew? It was he that the books of law
were given to.  And the jews cherish the books of law from the Old
testament a lot more than the Christians do.
> The chosen race are the White people and 
> described as White in the Bible.
Getting weirder by the minute.  The bible talks about chosen people,
not chosen colours.  And the chosen people of the old testament are
most certainly the jews which are not that "White" as a race.
> Jews falsely claim to be the chosen, 
> when in fact they are the race of Anti-Christs and enemies of God.
Tut tut.  Before Christ was born there was no-one to defend the cause
of God except jews.  Pretty hard to be the enemy of God that way.  And
the Lord made sure to press his point.  Whenever they failed to
properly acknowledge to be his chosen people, he plagued them in
various ways.  Just read the old bible.
The biblically oriented reasonings of
antisemitism are typically based on the following:
a) the failure of jews to acknowledge Jesus Christ as the messiah of
   *their* religion, later "properly" continued by Christians.  There
   is particular resent against the people demanding that Jesus be
   crucified (which he later was, by the Roman forces).
b) a few passages attributed to Jesus Christ, like the wedding where
   the invited guests would not come and instead kill the inviting
   servants, and where later people from the street are invited
   instead.  Interpretation: if the chosen people will not follow the
   invitation to heaven, the path will be open for others (namely the
   heathens).
c) Several problematic passages by Paul (one of the really dubious
   characters of the New Testament) where he actually claims that any
   attempts at keeping the law are in fact evil because they insinuate
   that one does not believe in the saviour.
This is particularly problematic as Jesus himself claimed that he has
not come to dissolve the law, but fulfill it, and that no letter of
the law no matter how tiny was to be disregarded.
Small wonder Paul was exiled from the society of the early Christians
and sent to the heathens instead of teaching jews, in particular
because of strong dissension with Jacobus, the spiritual leader of the
early Christians.  Paul and his opinions, even his antisemitism, have
however prevailed and become quite popular with an overwhelming number
of heathens.
Tough luck.
Sorry for the off-topic ramblings.
-- 
David Kastrup                                     Phone: +49-234-700-5570
Email: dak@neuroinformatik.ruhr-uni-bochum.de       Fax: +49-234-709-4209
Institut f=FCr Neuroinformatik, Universit=E4tsstr. 150, 44780 Bochum, Germa=
ny

In article 
<19970109120700.HAA06137@ladder01.news.aol.com>, 
lbsys@aol.com says...
>
>Very much so. Although within the last 500 years, a 
hell of a lot of the
>in-betweens have been cleared up to a great extent. 
We know now that
>lightnings are electric phenomena and it is not the 
god Thor hurling his
>javelin at us... (which has diminished the influence 
of religion quite a
>bit  ;-)
>
What is certain is that a great number of the old "in 
betweens" have been cleared up to a great extent. We 
have also generated a whole new set of "in betweens," 
have we not? What exactly is a strange attractor, 
gravity, inertia? Is the cat really alive or dead? Why 
do chaotic systems bifurcate rather than trifurcate? 
Etc., etc.
Doug

Subject: Re: Toy Radiometer
Newsgroups: sci.physics
References: <96122715310331566@engineers.com> <19970111134501.IAA15809@ladder01.news.aol.com>
Distribution: 
: The vanes effectively act in a similar way to the aerofoil section of a
: wing.
: Radiation warms the black surface and the gas molecules in contact with
: the surface are heated in turn. The warm gas rises and a pressure drop is
: created in this region. A pressure gradient is formed and the gas 'pushes'
: the vane in an attempt to restore the pressure equilibrium. As the gas is
: constantly being heated the vanes rotate.
X-Newsreader: TIN [version 1.2 PL2]
This doesn't make sense. Look, if the air on the black side of the vanes 
gets warmed and rises, then the pressure on the white side should be 
greater than the pressure on the black side and therefore, the black 
sides would get "pushed" around. The black sides would lead. However, my 
radiometer (which does indeed contain air) rotates the other way (white 
sides leading). 
The correct explanation is that radiation (light) strikes the black side, 
energizing the air molecules in the process. The molecules collide with 
the black side of the vanes and each other producing a change in momentum 
which is greater than the change in momentum imparted by the radiation 
bouncing off the white side of the vanes. Greater change in momentum 
means greater imparted force (Newton's second law), and therefore, the 
vanes rotate with the white sides leading.
			Hope this helps.
                          -- Joe Heafner
*************************************************************************
*             Joe Heafner, Astronomy and Physics Instructor             *
*                       Work:(704)327-7000, x. 246                      *
*heafnerj@mercury.interpath.com, http://mercury.interpath.net/~heafnerj/*
*************************************************************************

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lbsys@aol.com wrote:
> 
> Im Artikel <32D65F09.7646@ccf.nrl.navy.mil>, David Schaafsma
>  schreibt:
> 
> >My point was that the months of the year are not random to humans.  We
> 
> But this is what astrology claims just the same! (And a bit more, all with
> a lot of hokeypokey of course). But maybe you're in the know and can 
I don't claim to know what the correlation is, just that the statistical
evidence is not enough to prove that astrology has a real scientific
basis.  I have always understood astrology to include things like the
influence of the planets on people's psychological makeup.  If that's
not what you mean, then perhaps it is best to choose another term. 
> 
> >If you are getting some anomalous results in Switzerland, why not try
> >this in another country?
> 
> It took the money of a multi-millionaire (and the greed and the time and
> the impetus etc.) as well as a given database (recorded marriages with
> birth dates) to do that. Do you have: money, time and a good database?
> Hey, why not try in Las Vegas? I'm sure they keep track on personal 
That's a good idea.  But it's not my research.  The onus of proof is on
you.  If you want to make scientific claims about this, your work has to
stand up to scientific criticism.
> 
> >Does the astrological correlation hold up in
> >China?  If you could show that, then I would begin to
> >think that there was something worth investigating.
> 
> Now that's just too nice of you. Sure, the world is waiting for David
> Schaaafsma, PhD, to answer the question if something's worthwhile
> investigating.
My intent was not to belittle you or say that you're wasting your time.
I would be skeptical of any purely statistical correlation.  One of the
questions that science must address is "what is the mechanism?" and you
must then formulate a hypothesis which allows you to test that
mechanism.  My understanding of your original post was that you were
claiming that your statistical correlation was proof of a scientific
basis for astrology.  Again, I don't mean to speak down to or deride
anyone personally, but I am sticking to my contention that you have not
established a scientific basis for astrology.  And I re-iterate my point
that statistics do not "prove" anything of this nature.
I would like to add another point.  There is a danger in this of which
you may or may not be aware.  Astrology in general is harmless and may
even be useful or comforting to some people, and if you demonstrate
anything beyond a statistical correlation, I will be the first to
congratulate you.  But to bypass the scientific method is to open the
door for a lot of very odious ideas, such as creation science.  (There
is a big thread in this group about creation vs. evolution, as I'm sure
you're aware.)  Creationists would love nothing more than to pick and
choose what parts of science they believe.  In point of fact, science is
defined by its method.  Your theory *must* be falsifiable, verifiable,
and the results reproducible, among other things.  As this is a
newsgroup devoted to physics, I think it pays to be careful about this. 
-- 
David T. Schaafsma, PhD
Optical Sciences Division, Infrared Materials Group
U.S. Naval Research Laboratory
Washington, DC

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If you need any kind of physics data i'll be happy to help you if i can 
I am deadly interested in data about :
the height of the ionosphere and the electromagnetic field off the 
planet

> "Constants", as we define them, seem to have one thing in common; they
> relate to the interrelationships of one dimension to another.  
Allow me to add to this.  
	Mathematical constants have one thing in common (one thing that
those of us whose last names are not Gauss or Erdos can grasp at any
rate):  They have precise mathematical definitions.
For instance   e = lim   (1+1/x)^x as x grows unbounded.
	Physical constants such as epsilon naught (That's the one in
Gauss's law for electric fluxes in free space) are not precise
mathematical constants. However they are so close to precise that we can
simply pretend that they are.  This approach works quite well for
everything from modeling solenoids to predicting the age of the universe. 
asdf,
A.J. Tolland
ajt@wpi.edu         
http://www.wpi.edu/~ajt
moderator: wpi.massacademy

Mario Desiderio wrote:
> 
> Dear Friends,
> 
> Could you please email me a simple Formula to calculate the exact weight
> related to teh position on the earth given in latitude and longitude.
> 
> I just know that the mass remains fixed and the G force chenges
> according  to latitude and longitude please tell how to calculate the G
> changes accordinghly.
The weight forces change slightly, and the longitudinal variation
depend upon the positions of the sun and moon.  Is that what you're
looking for?
-- 
D.
mentock@mindspring.com
http://www.mindspring.com/~mentock/index.htm

Terran@pwshift.com wrote:
>the slim proofs of Evolutionary Theory
Why do you call 3.5 billion years of evidence either "slim" 
or "proof"?
You also denied the existence of transitional forms.  Then
I have to ask you:  exactly what do you expect a transitional
form to be?  Why do you think that hypothetical form is a 
better example of what evolution "should" expect, than the 
tons of forms conventionally considered "transitional"?  Be,
er, specific [sorry about that].
---mellyrn
------------------------------------------------------------------
speaking only for myself

Boris Mohar (borism@interlog.com) wrote:
: On 12 Jan 1997 17:01:26 GMT, kfoster@rainbow.rmii.com (Kurt Foster)
: wrote:
:>  "I am a HAL Nine Thousand computer Production Number 3.  I became
:>operational at the HAL Plant in Urbana, Illinois, on January 12, 1997."
:>--  "2001 a space odyssey" -- a novel by arthur C. Clarke
:   And if you shift right the letters HAL you will get his dady's name.
:
  "Hal (for *H*euristically programmed *AL*gorithmic computer, no less)
was a masterwork of the third computer breakthrough. ..." -- "2001 a space
odyssey" -- a novel by Arthur C. Clarke
  The fact that shifting ther letters by 1 gives "IBM" is simply a
coincidence.  Arthur C. Clarke says so.
  There was a segment about Hal's birthday om the January 12 installment
of the NPR program "Weekend Edition".  One thing about HAL that DID come
from an earlier computer:  the program included a playback, from archival
tape, of the very first "speaking" and "singing" by a computer -- the
Illiac IV, in Urbana, Illinois.  The year was 1962.  The "speaking" was a
recitation of Hamlet's soliloquy "To be, or not to be...".  And the very
first song "sung" by a computer was, of course, "Daisy, Daisy"...

In article <32d8371a.0@cfanews.harvard.edu>,
   trothman@cfa0.harvard.edu (Tony Rothman) wrote:
>I am searching for some plays on science,
>excluding the usual suspects: Brecht, Durenmatt,
>Capek.  Any leads appreciated.
>trothman@pppl.gov
>
Some of Tom Stoppard's recent plays (e.g. "Arcadia") may qualify.
Bob Michaelson
rmichael@nwu.edu

In article <5be4n2$de8_001@library.nwu.edu>,
   rmichael@nwu.edu (Bob Michaelson) wrote:
>In article <32d8371a.0@cfanews.harvard.edu>,
>   trothman@cfa0.harvard.edu (Tony Rothman) wrote:
>>I am searching for some plays on science,
>>excluding the usual suspects: Brecht, Durenmatt,
>>Capek.  Any leads appreciated.
>>trothman@pppl.gov
>>
>Some of Tom Stoppard's recent plays (e.g. "Arcadia") may qualify.
>
>Bob Michaelson
>rmichael@nwu.edu
And, I forgot, "Breaking the Code" by Hugh Whitemore, about Alan Turing.
Bob Michaelson
rmichael@nwu.edu

Ken Fischer  wrote:
> gooral@sentex.net wrote:
> : Hi Ken!
> : You look to know so much, so I hope you can explain one thing to me.
> : The light ray grazing the Sun is bent. Einstein predicted the angle 
> : as !.75 arcsec.
> : Space curvature accounts for half of this angle.  
> : Can You tell me what accounts for the other half?
> : Jan Gooral             gooral@sentex.net
> 
>         I included sci.physics.relativity in the followup,
> I'm sure someone there knows the answer.
>         
>         Originally, in a 1911 paper, Einstein predicted half
> that angle (1.75, not !.75, I think), and all of that was
> based on Newtonian gravitation and the Principle of Equivalence,
> or simply the acceleration of gravity applied to all motion.
>         The other half (as my best guess) is caused by a hidden
> variable velocity (my terminology) affecting the coordinate
> system (that would be the spacetime curvature supplement, I think).
If I plug in the numbers for the sun: 2.0E30 kg, and the sun radius ==
perihelion distance 7.0E8 m, and the speed 3.0E8 m/s for a probe entering
the solar system, then Newton's theory (giving a hyperbolical path) will
produce an angle of 0.872 arc-seconds according to my calculations.
This is about half of 1.75.
I haven't seen the complete GR derivation of the 1.75 angle, but my own
hunch is that the difference from the newtonian path is due to time
dilation in the relativistic model. In the newtonian model the "probe"
(the photons) will gain speed as the perihelion is approached, but
according to relativity the energy increase is manifested as blue-shift,
not a change in speed. So the angular deflection of the photons will be
affected more by the gravitational acceleration than what the newtonian
theory predicts.
Correct me if I am wrong.
-- 
Bjorn Danielsson  
http://www.algonet.se/~bonus

Operator (root@power7200.ping.be) wrote:
> In article <19970111094800.EAA12474@ladder01.news.aol.com>,
> 	lbsys@aol.com writes:
> >Im Artikel <5b38ir$cu@colossus.holonet.net>, russell@news.mdli.com
> >(Russell Blackadar) schreibt:
> >
> >>And btw, he was not waving the gyroscope -- he was simply following
> >>the gyroscope's own motion, i.e. its precession.
> >
> >Yup...
> >
> >>  He would not have
> >>been strong enough to stop it even if he tried
> >
> >who knows?
> >
> >> -- but if he were
> >>capable of such a feat, and did it, the loose end 
> >>of the gyro would have fallen downward normally. 
> >
> >Are you sure about that? We're talking of, let's say a gyro whichs
> >horzontal axis is bolted on one end, thus the whole axis could only move
> >up or down rotating around the bolt like a signal arm, ok?
> >
> >So: Does it make a difference (in falling down) if the flywheel is
> >spinning or at standstill? Intuitively I'd say: YES - what's your opinion?
> Hey Lorenz,
> I think you should look up the spinning fish in that iglo again ;-)
> (Russell is right)
Hmmm, I think my statement was actually a bit hasty and not
*strictly* correct.  If you had infinitely rigid materials
constraining it to move only in a vertical plane, and infinitely
slippery lubricants to allow the joint to move despite having 
gigantic torque act perpendicularly to it, then the Earth
would be turned by the gyro mounting in such a way that no
difference from a "normal" fall would be detectable.  But in
principle, such turning of the Earth *would*, in fact, affect
the motion so it would not be precisely the same as if a 
non-rotating gyro fell from the same position.  So Lorenz is
also right, I think.  Just a question of principle vs.
detectability.
In practice, of course, no such materials or lubricants exist.
Precession is effectively irresistible, unless (counterintuitively)
you apply torque at right angles to it.  And that, btw, would have
been quite within the capability of a strong man in this case.
(Or, depending on how he held the gyro, perhaps an *unusually*
strong man.)  I just don't think he did it that way, from what 
I understand of the description.
> cheers,
> Patrick.
--
Russell Blackadar,   russell@mdli.com

: Joseph H Allen wrote:
: > 
: > Here are some paradoxes:
: > -- black ravens
: > Now the negation of "all ravens are black" is "all non-black things aren't
: > ravens".  The two statements are logically equivalent.  Thus all of the
: > non-black things you find which aren't ravens (your red coat, the white
: > ceiling, etc.) also support your generalization 
: > that "all ravens are black".
   Hm, isn't there a name for this paradox? 'Hempel paradox' or
something? I really like it: Some lazy ornithologist on a rainy
day could investigate whether all ravens are really black just
by going around his room and noting objects which are not ravens
and which are not black. 
--
------------------------------------------------------------
Kresimir Kumericki  kkumer@phy.hr  http://www.phy.hr/~kkumer
Department of Physics, University of Zagreb, CROATIA
------------------------------------------------------------

On 12 Jan 1997 23:43:04 GMT
ale2@psu.edu (ale2)
as message <5bbsu8$v48@r02n01.cac.psu.edu>
-- posted from: alt.atheism:
>|In article 
>|varange@crl.com (Troy Varange) writes:
>|
>|> > A PhD isn't useless. True, the knowledge you are digging up
>|> > is very specialised, but the skills you learn while digging
>|> > are very important: determination, skepticism, thought,
>|> > rigour, etc.
>|> 
>|> Ha, a PHD bearer is more likely to be a clueless mediocrity
>|> than the common man without the degree, at least in the USA.
>|> 
>|
>|But who gets hired at Microsoft Corp.?
Clueless fucks who write garbageware for a power-mad marketing wizard.
Erikc -- firewevr@insync.net
Fundamentalism -- a disease whose symptoms include
diarrhea of the mouth and constipation of the brain.
Wanna see how sick some fundies are?
http://www.christiangallery.com/    (home page)
http://www.christiangallery.com/sick1.html#bugger (sicker than ever)
/* Finest Christian porn on the 'Net */

In article , meron@cars3.uchicago.edu wrote:
>In article <32D6F217.4A6B@quadrant.net>, "Bruce C. Fielder"
>  writes:
>>meron@cars3.uchicago.edu wrote:
>>
>>> The energy isn't really high enough for the creation of particles.
>>> Given center of mass corrections etc. you need /gamma of 5-6 or so,
>>> meaning v/c around 0.98 or higher.
>>> 
>>True enough, I stand corrected.
>
>However, I noticed that I underestimated the damage potential a bit.  
>While not enough for particle creation, the velocity is high enough to 
>break nuclei to pieces.  So one can expect a shower of neutrons which, 
>in turn, will activate some of the surrounding stuff.  Fortunately, 
>since nuclear cross sections are so much smaller then atomic ones, 
>most of the energy will be dissipated in purely electromagnetic 
>interacions, creating a pretty hot plasma and lots of x-rays.
Cool.  Thank you.
The proper way to figure out what the recipient of the Dime 'O Death would 
experience, I assume, would be to work on a particle level: use a center of 
mass frame, do the collision, and assume output radiation of whatever 
intensity I can get out of a collision that conserves momenergy.  (I am 
working with worst case, after all.)  If I do not see that the photons in 
question have enough energy for pair creation, then we are somewhat 
radioactive-free.  If the photons do not have enough energy to exceed the 
binding energy of a nucleus, then we are essentially completely free of 
radioactives.
Scott
Scott Ellsworth          scott@eviews.com
"When a great many people are unable to find work, unemployment 
results" - Calvin Coolidge, (Stanley Walker, City Editor, p. 131 (1934))
"The barbarian is thwarted at the moat." - Scott Adams

On 12 Jan 1997 16:36:55 GMT
czar@freenet.edmonton.ab.ca ()
as message <5bb3v7$am4$1@news.sas.ab.ca>
-- posted from: alt.atheism:
>|(Singing)
>|
>|Immanuel Kant was a real pissant,
>|Who was very rarely stable,
>|Heidegger, Heidegger, was a boozy beggar
>|Who could think you under the table,
>|David Hume could out-consume
>|Schopenhaur and Hegel,
>|And Wittgenstein was a beery swine
>|Who was just as shloshed as Schegel!
>|
>|There's nothing Nietzsche couldn't teach ya
>|'Bout the raising of the wrist!
>|Socrates, himself, was permanantly pissed!
>|
>|John Stuart Mill, of his own free will,
>|On half a pint of shandy was particularly ill,
>|Plato, they say, could pack it away, 
>|Half a pint of whiskey every day, 
>|Aristotle, Aristotle, was a bugger for the bottle,
>|Hobbes was fond of his dram,
>|And Renee Decartes was a drinken fart, 
>|"I drink, therefore I am!"
>|
>|Yes, Socrates himself is particularly missed, 
>|A lovely little thinker, but a bugger when he's pissed!
>|
Where does this song come from?
>|--
>|******************************
>|   Me fail English?
>|   That's unpossible!
>|             - Ralph Wiggum
>|******************************
Erikc -- firewevr@insync.net
Fundamentalism -- a disease whose symptoms include
diarrhea of the mouth and constipation of the brain.
Wanna see how sick some fundies are?
http://www.christiangallery.com/    (home page)
http://www.christiangallery.com/sick1.html#bugger (sicker than ever)
/* Finest Christian porn on the 'Net */

George X. Kambic Ph.D. wrote:
> John Murphy wrote:
> [...]
> > Rather than interference, I say the effect is due to a filtering
> > process that acts on a population that is resident in the slit screen.
> [...]
> The need for these explanations goes away with QED theory.
No way! There has been 60 years or so of this absurd situation
in which interference is supposed to be at work in quantum 
scattering.
We have been told that this is caused by the dual wave/particle
nature of light and matter. 
However, there is no explicit representation for either
  1 The process of interference
  2 The "switch" between the localised effects of particles,
    and the distributed effects of waves,
anywhere in QED. i.e. the maths does not contain interference
and there is no straight model of how it reconciles with particles.
The case I make is that the interference model ignores the properties
of the quantised structure of the matter in the slits.
My article 
  http://www.murphy.gen.nz/murphy/sham_idx.htm
presents a straight clear model (not facile explanation) as to how
the structure of the slit screen determines the spectrum of 
energies/momenta that the slit screen can exchange with
particles. Further, I demonstrate as to how this spectrum 
becomes superimposed on the particle beam directed at the 
slits.
The theory is grounded in, and consistent with, exactly the same 
principles that lead to an atom being only able to exchange energy
with photons of certain exact energies.
Finally, it is consistent with the Hilbert space representations
used in QED.
John
Schroedinger's cat leave you half dead?
  Conciousness-Induced Collapse leave you feeling a little deflated?
Then try 
  http://www.murphy.gen.nz/murphy/sham_idx.htm

Dear Friends,
Can any of you please tell with very simple words how to understand why
a flying bird that is just maintaining its position inside the wagon of
a moving train at a given speed which is much higher than teh bird
itself.
Please explain me with simple words why the bird does not get smashed
against the wall of the wagon as the train moves with or without
acceleration or when it breaks.
Does the explanation for the above explains also why an airplane the
circles around teh same point on the earth it keeps the same point as
the earth rotates and on the other hand it does not find bellow itself a
different point of the earth ?
Thank you ver much for your explanations it will make a lot of yougsters
very happy and alos not so youngsters that frequently ask me these type
of questions,
Sincerely yours,
Mario Desiderio

In article <5b33e2$ga8@lynx.unm.edu>,   wrote:
>In article <32D4582F.695@ix.netcom.com>,
>Bill Oertell   wrote:
>>Mark Friesel wrote:
>>> 
>>> Sorry for asking a question that seems rather trivial, but I was
>>> wondering if someone could review, in a reasonable space, why black
>>> holes form and the conditions under which they do so.  Please reply to
>>> my email as well.  Thanks in advance.
>>> 
>>> Mark Friesel
>>
>>   As some folks have pointed out, the heat produced by internal fusion
>>in a star balances the force of gravity trying to make the star
>>collapse.  As the star uses up hydrogen, it starts "burning" other
>>elements--first helium, then other elements, all of which produce
>>thermal energy that to varying degrees balances gravity.  Eventually, it
>>tries to fuse iron.  
>>   Only problem is fusion of iron consumes energy rather than producing
>>it.  At this point, the core suddenly collapses.  The outer shell of
>>gasses follows the core, and the tremendous and sudden pressure quickly
>>creates all the elements heavier than iron and creates a supernova.
>>   If the star is large enough, no atomic force can keep the subatomic
>>particles apart.  Eventually the star will collapse into a mass so small
>>and dense that it's surface escape velocity will be greater than 186,282
>>mile per second.  That's when it becomes a black hole.
>>
>>                                 Bill
>Small quibble, Bill.  Solar mass sized stars don't supernova,
Sure they do! Just under special circumstances. They need to be part
of a close binary, and accrete material off the other star
at just the correct speed. When enough material collects, it undergoes
catastrophic fusion. Kaboom! Type I supernova.
[...]
>they blow off
>their outer layers in a "planetary nebula" and expand to red giant stage, and
>then just fairly quietly collapse to white dwarfs.  
This post-red-giant stage is VERY interesting, and not well understood.
Some stars blow off gas in several separate events, giving weird shapes
to the nebula. See an HST image of the Cat's Eye to see what I mean.
>Although the galaxy is
>filled with planetary nebulae (looking like smoke rings), there is no evi-
>dence of highly energetic SN events corresponding to them.
And on the other hand, some SN look a lot like planetary nebulae, like 
SN1987A's nebula. It may have been created in much the same way as a PN,
but the central star has two main differences: it weighed in at 20 or so
solar masses, and then it exploded. The nebula was heated in a giant flash,
rather than with a slow, steady stream of UV photons like most young
white dwarfs give off. There is a description of this in the February
issue of SKy and Telescope, celebrating 87A's tenth anniversary.
-- 
* Phil Plait, Pee Aytch Dee       pcp2g@virginia.edu 
* My home page-- http://www.astro.virginia.edu/~pcp2g/home.html
*      -->  Humor, supernovae, Bad Astronomy, Mad Science
*           and my daughter Zoe.

paschal  wrote:
>what a crazy argument.
>don't you think that GOD was smart enough to think up
>EVOLUTION???
>-P.
Thanks for your clear illustration of the subject of this thread.
Your argument is a not-too-subtle example of a logical fallacy.
Excerpted from:   http://www.bridge.net/~cmunns/fallacy.htm
----------------------------------------------------------------------
Begging the Question 
    1.Question-begging definitions: an argument commits this fallacy
      when it ensures its conclusion by using definitions which rule 
      out any other possibilities. 
      Example: True Americans support legislation which enacts trade 
               sanctions against our enemies.  Jones doesn't support 
               trade sanctions. Therefore, Jones isn't a true 
               American. 
    2.Circular arguments: an argument is circular if the very thing it
      is trying to prove (its conclusion) is assumed, though often 
      unstated, in its premises. 
      Example: The Bible is the revealed word of God. The Bible says 
               that God exists. Therefore, God exists.
----------------------------------------------------------------------
JeffMo
"A valid argument is not formed solely by ignorance." -JeffMo
"A valid argument is not formed solely by assertion." -JeffMo
Religion : Science :: Methamphetamine : Exercise
For email replies, remove the "dipstick." from my eddress.
It should be self-evident that I am not a dipstick.  ;-)

> : Wrong for special relativity's model of the twin paradox.  Because the
> : twins weren't both in uniform motion.  One accelerated.  In special
> : relativity, while velocity is relative, acceleration is not. 
> 
> : Look it up if you don't believe me.  Say, the relativity FAQ at
>          I may have gotten this from an old article,
> but which is it, velocity or acceleration that causes
> time dilation, I mean true slowing of clocks so they
> never read the same time when brought back together,
> even the ticks may coincide.
> 
> Ken Fischer 
Well Ken,  the answer about the acceleration is both.  Both acceleration
and velocity cause time dilation.  For acceleration, the time dilation will
change with time.  It is the acceleration which resolves the problem of the
twin paradox.  This is well documented as it is considered a very good
relativity problem.

Why is it that those who are so ardently for atonality (and nihilism
in general) are Jews, or are led by Jews?  If my memory serves me
correctly, wasn't the inventor of atonality Schoenberg, a Jew?
Why are you Jews so bent upon destroying traditional Western culture?
I must say, you've done a pretty damn good job so far.
- Heisenberg

erikc wrote:
> 
> >|
> >|Immanuel Kant was a real pissant,
> >|Who was very rarely stable,
> >|Heidegger, Heidegger, was a boozy beggar
> >|Who could think you under the table,
(edited song lines)
> >|
> 
> Where does this song come from?
> >|--
Monty Python.  It's the Philosopher's Drinking Song, sung by the
philosophy faculty at some Australian university.  I think Eric Idle
wrote it, but I couldn't be sure about that.  
-- 
David T. Schaafsma, PhD
Optical Sciences Division, Infrared Materials Group
U.S. Naval Research Laboratory
Washington, DC

Sir Terrance of SAL  wrote:
>Sometimes basic physics is forgotten. The speed of light is c, a constant,
>and therefore regardless of the energy of the light, the geodesic is the
>same. 
>Geodesics are velocity dependant not mass dependant (except, of course, 
>for the mass of the gravitating body) 
This is certainly true when the mass of one body (the gravitating
body?) greatly exceeds that of the other body (the orbiting body?). In
these cases the only mass that is important is the mass of the more
massive body. This is why say a 1 kg mass falls in the same manner as
say a 2 kg mass when dropped,
However, once the mass of the smaller body becomes a sizable fraction
of the mass of the larger body, i.e. both bodies start to become
equally massive you will need to know the masses of both bodies to
compute the geodesics. In this case, it is no longer true the path is
independent of the mass of the smaller body.
The point is the curvature of spacetime is affected by the masses of
all of the bodies in the system. When the mass on one body greatly
exceeds that of the other bodies of interest, then the center of mass
for the system is nearly the center of mass of the large body. Then
motion of the large body relative to the center of mass of the system
is essentially zero. But once the center of mass of the system no
longer corresponds to the center of mass of the largest body, its
motion relative to the center of mass of the system must also be
considered.

Hugh Young (hugh@young.wn.planet.gen.nz) wrote:
> In <32D5FE70.18D3@de.att.com> Norbert Kolvenbach  wrote:
> >Joseph H Allen wrote:
> >> 
> >> In article <01bbfdcb$f741e5a0$LocalHost@brian>,
> >> Brian Tozer.  wrote:
> >> 
> >> >> >> Here are some paradoxes: Now the negation of "all ravens are black" 
> is
> >> >> >> "all non-black things aren't ravens".  The two statements are
> >> >> >> logically equivalent.
> >> Now the statement "all non-black things aren't ravens" is logically
> >> equivalent to "all ravens are black".  Thus all of the non-black things 
> you
> >> find which aren't ravens (your red coat, the white ceiling, etc.) also
> >> support your generalization that "all ravens are black".
> >From "all non-black things aren't ravens" it follows, that "all ravens are 
> >black". But the reverse is NOT true, hence no equivalence!
> Yes it is. IF all ravens are black (no painted or albino ravens), then all 
> non-black things are not ravens.
> I have no trouble with each non-black thing I see - my computer but not my 
> printer, my hands but not my fax - adding to the stock of non-black things 
> that help to confirm the statement that all ravens are black. But you have to 
> admit that every black raven adds relatively substantially to the stock of 
> ravens, compared to the infinitessimal amount that every non-black non-raven 
> adds to the stock of non-ravens. Almost everything in the universe isn't a 
> raven.
> This is what Bertrand Russell called a veridical paradox. Strange but true.
> I have a problem with the equivalence though: A single non-black raven 
> DISproves the statement (or its equivalent), but neither non-black non-ravens 
> (like almost everything), black non-ravens (like my printer and fax), nor 
> black ravens (of course) will DISprove it or the equivalent. So are the 
> statements really equivalent? 
>   
> --
> Hugh Young, Pukerua Bay, Nuclear-free Aotearoa / NEW ZEALAND 
>             Ivory Soap - 0.7 grams of IMPURITIES in every 125 gram bar!
--
Russell Blackadar,   russell@mdli.com

Hugh Young (hugh@young.wn.planet.gen.nz) wrote:
...
> I have a problem with the equivalence though: A single non-black raven 
> DISproves the statement (or its equivalent), but neither non-black non-ravens 
> (like almost everything), black non-ravens (like my printer and fax), nor 
> black ravens (of course) will DISprove it or the equivalent. So are the 
> statements really equivalent? 
It would be rather odd if equivalent statements were *not* disproved
by the same thing (a single non-black raven).  So what's your problem?
--
Russell Blackadar,   russell@mdli.com