Subject: Re: Early 1950's SF film "The Magnetic Monster" and Thermodynamics.
From: gfp@sarnoff.com
Date: Sun, 27 Oct 1996 22:16:42 GMT
jac@ibms48.scri.fsu.edu (Jim Carr) wrote:
>gfp@sarnoff.com writes:
>>
>>This is a movie I saw on tv many times as a kid.
> I only saw it once, on Ch. 9 out of Windsor, Ontario, in the mid-70s
> after the second date with the young woman I married. Do I have to
> add that she is a trekkie? Anyway, thanks to this article, we will
> soon have it on videotape from Sinister Cinema.
>>After some 30 years., it's still fun to watch (one of the principle
>>players walks around with a pipe trying to look like Oppenheimer).
> The hero is a professor at "State University" (even though it
> seems to be set mostly in Canada), who boldly pushes the Deltatron
> past its limits (mucho sparking) and saves the planet.
>>A lone (mad?) scientist, accidently creates an atom of a superheavy
>>element that is radioactive , but in reverse.......
> I am sure it is a magnetic monopole. A very hungry monopole.
> My recollection is that it was created in a regular old experiment
> after something was bombarded with X MeV deuterons for N hours.
> Pion condensates were being muttered about at the time, with a
> local columnist wondering if the new heavy ion machine might
> destroy the city if it made one (how he got his hands on the
> proposal we will never know), so it was semi-plausible.
>>It draws in electric charge (energy) constantly, converts it to mass,
>>and doubles its size every eleven hours. (I won't say what happens if
>>it doesnt get fed on time.).
> Doesn't it want all of that energy during a short time when it
> does its doubling thing? Once they reach the capacity of the
> north american grid, they *know* they are in trouble. And how
> do they know? Here is the good part: theoretical calculations
> on the MANIAC at Los Alamos!
>>So is this absolutely impossible, or not?
> Absurdly funny, yes. The film of the sparkler run in reverse does
> suggest a little entropy problem, but they left enough details vague
> that it could work out OK globally.
Great Fun-the raw material for the experiment is "serene-ium"! The
"Maniac" is an IBM card sorter! Look for the companion film
"GOG"-MGM/UA may be relasing them, for real, in color 'scope and 3d
soon, if people ask for them. Lets hope!!!! jerry pulice
Subject: Re: what Newton thought
From: mls@panix.com (Michael L. Siemon)
Date: Mon, 28 Oct 1996 02:50:03 -0400
In article <551bk4$p11@ssbunews.ih.lucent.com>, lew@ihgp167e.ih.att.com
(-Mammel,L.H.) wrote:
+I feel pretty sure that Newton's philosphy, as well as his
+physics, held sway until 1900. Note that Einstein admitted
+to being influenced by Mach, but not Michelson-Morley.
Ummm, as I read the _scholia_ in Newton's _Principia_, there is
a hint of belief in absolute space and time, but a *practical*
admission that we cannot get there from what we have presented
to us in the data, which *only* support relative quantities.
This is quite independent of late 19th or early 20th century
reworkings of the issue.
What, exactly, Mr. Mammel, do *you* contend to be Newton's
"philosophy" on these matters -- and can you cite Newton to
exhibit your point? I suspect that I can quote _Principia_ to
undermine any very plausible absolutism you might attempt to
extract from it.
That Einstein was not (or may not have been) influenced by
Michaelson-Morely is neither here nor there. Yes, he *was*
influenced by Mach. So? Are you claiming that Mach was not
influenced by Newton? :-) I see a substantial philosophical
similarity of Mach's position with some of the _scholia_ on
motion in the _Principia_. Do you disagree? If so, why?
Michael "hypotheses non fingere" Siemon.
--
Michael L. Siemon mls@panix.com
"sempiternal, though sodden towards sundown."
Subject: Re: Questions about Engeneering Physics
From: Robert Dorman
Date: Mon, 28 Oct 1996 01:02:06 -0800
gfp@sarnoff.com wrote:
>
> jamcorp@world.std.com (Jonathan Priluck) wrote:
>
> >In article <326FA834.617B@ornl.gov>, C. Wayne Parker wrote:
> >>Slither (Jack) wrote:
> >>>
> >>> I am a college freshman considering a major in Engeneering Physics. I
> >>> have decided it would be a good idea to research this further: Is
> >>> anyone out there involved in this profession? Does anyone have any
> >>> advice as to whether this is a 'good move'? How is the job
>
> My BS is in Engineering Science, MS in EE, and I don't regret it for
> a moment.
>
> I was advised at an early age that to "do" pure physics as a
> profession, I would have to go thru for a PHD, and would most likely
> end up teaching (doctor means "teacher"). I really wanted to be a
> "phyisicist", growing up during the cold war, but don't regret
> becoming an EE at all.
>
> I only "job-shop"-a less pretentious term for "consult", and am very
> pleased with the lack of politics I have to put up with. Tenure and
> department politics are probably far worse than any industrial
> political process, as engineering is a meritocracy. (it is also very
> Darwinian). Sort of forces you to keep current.
>
> Learning is a life long process, and what you learn does not have to
> apply exactly to how you earn your living. Good Luck! jerry pulice.
I have a BE in Engineering Science from SUNY at Stony Brook ('70).
I've worked an an EE both "direct" (some people call this "permanant"
employment; ain't no such thing!) and as a "shopper"
(consultant/independant contractor/job-shopper). There's nothing wrong
with the field you've chosen. It's all up to you. My advice would be:
1. Be real good at it.
2. Don't count on "job security"
3. Personality and self esteem ave very important. You will
get knocked down plenty of times so if you don't already
feel real good about yourself, fix it.
4. Be a team player, not a loner
5. Don't come accross as a flake; even if you have to pretend,
act as mainstream and conventional as possible. There are
alot of "characters" in the field, but when downsizing time comes...
6. Document everything you do, even if you're not told to. Keep
copies (non-classified, of course) at home. Cover Your Ass!
7. While you're still in school, make contacts and keep notes
on those people you may need help from later in your career.
8. Start saving a portion of your salary from your first paycheck on,
as "unemployment insurance." You will probably need it.
9. When you interview for a job, remember, what you see is what you
get. Don't rely on promises of salary increases, promotions,
expanding business, fast-track opportunities, etc. You've
got to be able to live with the situation just as it is when
you walk in the door, because in all likelyhood, that's
the way it's going to stay (or get worse).
10. If you are job shopping, update your resume the day you start work
and let the shops know you'll probably be available in a few
weeks (you probably will! although some of my assignments
lasted over a year, 3 months is typical, but companies often
get $queezed money-wise and can their shoppers to cut
costs, making the directs work overtime to pick up the
slack.
11. Remember, if you're a direct engineer, you probably won't get
overtime pay (you are 'exempt') so count on working long
hours gratis.
12. If you can, get a backup field like business or accounting. I'm
going after an accounting degree now, because I havn't found
any engineering around here and I don't want to move. Not
every company needs an engineer, but most need an
accountant. Plus, it helps in your engineering if you end up being
a cont-account manager on a project.
13. Don't badmouth anybody, no matter how much a jerk they are;
the walls have ears and word gets around.
Sorry for the lengthly reply and ataching my reply to a reply; I didn't
have the original message. Best wishes.
--Bob
Subject: Re: Questions about Engeneering Physics
From: Robert Dorman
Date: Mon, 28 Oct 1996 01:02:06 -0800
gfp@sarnoff.com wrote:
>
> jamcorp@world.std.com (Jonathan Priluck) wrote:
>
> >In article <326FA834.617B@ornl.gov>, C. Wayne Parker wrote:
> >>Slither (Jack) wrote:
> >>>
> >>> I am a college freshman considering a major in Engeneering Physics. I
> >>> have decided it would be a good idea to research this further: Is
> >>> anyone out there involved in this profession? Does anyone have any
> >>> advice as to whether this is a 'good move'? How is the job
>
> My BS is in Engineering Science, MS in EE, and I don't regret it for
> a moment.
>
> I was advised at an early age that to "do" pure physics as a
> profession, I would have to go thru for a PHD, and would most likely
> end up teaching (doctor means "teacher"). I really wanted to be a
> "phyisicist", growing up during the cold war, but don't regret
> becoming an EE at all.
>
> I only "job-shop"-a less pretentious term for "consult", and am very
> pleased with the lack of politics I have to put up with. Tenure and
> department politics are probably far worse than any industrial
> political process, as engineering is a meritocracy. (it is also very
> Darwinian). Sort of forces you to keep current.
>
> Learning is a life long process, and what you learn does not have to
> apply exactly to how you earn your living. Good Luck! jerry pulice.
I have a BE in Engineering Science from SUNY at Stony Brook ('70).
I've worked an an EE both "direct" (some people call this "permanant"
employment; ain't no such thing!) and as a "shopper"
(consultant/independant contractor/job-shopper). There's nothing wrong
with the field you've chosen. It's all up to you. My advice would be:
1. Be real good at it.
2. Don't count on "job security"
3. Personality and self esteem ave very important. You will
get knocked down plenty of times so if you don't already
feel real good about yourself, fix it.
4. Be a team player, not a loner
5. Don't come accross as a flake; even if you have to pretend,
act as mainstream and conventional as possible. There are
alot of "characters" in the field, but when downsizing time comes...
6. Document everything you do, even if you're not told to. Keep
copies (non-classified, of course) at home. Cover Your Ass!
7. While you're still in school, make contacts and keep notes
on those people you may need help from later in your career.
8. Start saving a portion of your salary from your first paycheck on,
as "unemployment insurance." You will probably need it.
9. When you interview for a job, remember, what you see is what you
get. Don't rely on promises of salary increases, promotions,
expanding business, fast-track opportunities, etc. You've
got to be able to live with the situation just as it is when
you walk in the door, because in all likelyhood, that's
the way it's going to stay (or get worse).
10. If you are job shopping, update your resume the day you start work
and let the shops know you'll probably be available in a few
weeks (you probably will! although some of my assignments
lasted over a year, 3 months is typical, but companies often
get $queezed money-wise and can their shoppers to cut
costs, making the directs work overtime to pick up the
slack.
11. Remember, if you're a direct engineer, you probably won't get
overtime pay (you are 'exempt') so count on working long
hours gratis.
12. If you can, get a backup field like business or accounting. I'm
going after an accounting degree now, because I havn't found
any engineering around here and I don't want to move. Not
every company needs an engineer, but most need an
accountant. Plus, it helps in your engineering if you end up being
a cont-account manager on a project.
13. Don't badmouth anybody, no matter how much a jerk they are;
the walls have ears and word gets around.
Sorry for the lengthly reply and ataching my reply to a reply; I didn't
have the original message. Best wishes.
--Bob
Subject: Re: Anti-Gravity Device?
From: "S. Smith / R. Bourgeois"
Date: Sun, 27 Oct 1996 09:13:03 -0800
Sorry for budding in like this in the middle of a thread...with a naive
question on top of that!
On the comment that we can't cancel gravity because it is always an
attractive force.... If gravity is a wave, then by definition, can't
you cancel any wave's effect by synchronizing it with a 180deg out of
phase parallel wave? They do it with sound! Theoretically then, isn't
it possible with gravity? An "Anti-gravity" beam like in the Jetsons!!!
:)
Thanks,
Ray
-------
Peter Diehr wrote:
>
> nervous wrote:
> >
> > So, anti-gravity...is it good or is it bad?
> >
>
> In the ordinary sense, it just isn't possible ... that's because
> gravity always attracts.
>
> > Remember that Ytrium-Barium stuff that dreams were made of? You
> > know...cold fusion?
>
> You're thinking of high-temperature superconductors.
>
> > Well, the first time I ever laid me eyes on it, it was
> > being demonstrated in my 1st year physics class (quite a while ago....).
> > Anywho, I noticed that the little piece of whatever that was used to
> > 'float' above the Ytrium-Barium cake, once started spinning (with the aid
> > of the professors pencil), it only spun.....
> >
>
> The floating was due to magnetic repulsion. It's called the Meisner effect.
>
> > Ahhhhh, never mind....
> >
>
> OK.
>
> > I don't think that anti-gravity is the key for any kind of intergalactic
> > propulsion system....
> >
>
> OK.
>
> > Let's talk about why witnesses report that UFOs have a wobbly trajectory
> > and how a friend of mine (while in Nepal) witnessed a Vedas meditate then
> > rise above the ground and have this same 'wobbly' look to him. Could it be
> > that UFOs and my friends swami-dude were utilizing the same quantum
> > consciousness? Sorta like UFOs and the Ghadi-guy were in our Universe and
> > another one (a higher one) at the same time?
> >
>
> Seems very unlikely to me. Of course, if they were both inhaling, who knows?
>
> Best Regards, Peter
Subject: Re: What is the Cause of Time Dilation?
From: savainl@pacificnet.net (Louis Savain)
Date: Mon, 28 Oct 1996 04:50:50 GMT
In article <5505ut$c9j@eri.erinet.com>, kenseto@erinet.com (Ken Seto)
wrote:
[I just have to respond to Ken Seto's post before my temporary absence
from usenet. If I can squeeze in the time I may be able to contribute
sporadically in the next few weeks.]
>savainl@pacificnet.net (Louis Savain) wrote:
>
>>In article <54tfsp$4qa@eri.erinet.com>, kenseto@erinet.com (Ken Seto)
>>wrote:
>
>>>savainl@pacificnet.net (Louis Savain) wrote:
>>>
>>>>In article <54ooj3$7fk_005@pm0-61.hal-pc.org>, charliew@hal-pc.org
>>>>(charliew) wrote:
>>>
>>>>>In article <326f17a7.261166@news.pacificnet.net>,
>>>>> savainl@pacificnet.net (Louis Savain) wrote:
>[...]
>>>
>>>Time dilation is the result of a different definition for a second in
>>>different inertial frames. In other words, the duration of a second is
>>>different in different frames by definition. Einstein did that to
>>>maintain the constancy of the speed of light in all frames. What about
>>>the slowed clocks? Why are they seem to tick slower? The answer to
>>>these questions are as follows:
>
>> Ken even though I agree with you that time dilation is a direct
>>consequence of making the speed of light constant mathematically, I
>>don't think that Einstein just decided to do that our of the blue. I
>>would bet money that somehow Einstein got wind of the MM null result
>>before submitting his paper for review. Does anyone here know whether
>>or not the SRT paper was submitted before of after the MM experiment?
>
>It was based on Maxwell's physics and the null result of the MMX.
>Maxwell's physics implies that the measured speed of light (E-M waves)
>is a constant c in all the directions as measured (Mu and epsilon are
>measured quantities) in the various Labs on earth. This does not mean
>that the measured light-speed has the same constant value in different
>inertial frames. However, that was Einstein's interpretation of
>Maxwell's physics.
Not a bad interpretation on the part of Einstein, I would say,
considering that there is really no such thing as an "earth frame".
The earth is constantly moving from one frame to another and MMX gives
the same result regardless of the time of year. Are you saying that
this is negligible? I don't think it is.
>As to the null result of the MMX, I had a long discussion on this with
>Brian Jones under the thread "Constancy of the Speed of Light--Purely
>Mathematical?" In so far as I know he finally agreed with my
>explanation. The explanation for the MMX null result is as follows:
>
>The underlying processes of the MMX:
>The MMX was performed in an enclosed Lab and therefore all the
>apparatuses in the Lab can be considered to be in the same inertial
>frame. This means that all the apparatuses in the MMX Lab had the
>same absolute motion. Now consider a light pulse that was generated
>from a source within the Lab, it was speed toward the target at an
>absolute speed of Ca. By the time it reached the old location of the
>target, the target had already moved to a new location. Therefore, it
>took the light pulse a little longer to reach the target and thus the
>speed of light as measured by the target was c which had a smaller
>value than Ca and c was the measured light-speed of the Lab frame.
Ken this makes no sense, IMO. Sorry. How do you know the target is
not moving toward the light beam?
>The above underlying processes imply that all the material systems
>within an inertial frame are in a state of receding motion from all
>the light pulses that are generated within the same frame. In other
>words, there is no c+v situations within the MMX apparatus. This
>description is true in all the directions.
In all directions? You're kidding me? I can't see how Brian Jones
could agree with this. I know I don't. What you are doing is making
an absolutely untestable assumption that, regardless of the absolute
velocity of the measuring equipment and the lab, the target is always
receding from the light beam.
>Now consider the MMX
>apparatus: The two mirrors at the end of each arm act as light
>sources. The light rays that are reflected from the two mirrors will
>travel an equal distance toward the silvered mirror that will
>recombine them. The silvered mirror is in a state of receding motion
>from both the light rays at the same rate and therefore, both light
>rays will arrive at the silvered mirror in phase and thus there is no
>phase shift showed up in the interferometer. Thus we have the null
>result of the MMX.
I'm sorry. I can't buy this explanation at all. According to your
logic, regardless of the absolute direction of the laboratory, the
target is always moving away from the source. You actually believe
this is logical? This is total hogwash, Ken. I apologize for being
so blunt but I can't side with this. No sir! Otherwise my
credibility and my continued progressive participation in this
discussion would be in jeopardy. Maybe you have something else in
mind that did not properly translate into words.
>[...]
>
>>>2. If you want to compare the passage of time using clocks you must
>>>use one frame as standard and reset all clocks in the other frames
>>>according to this standard.
>
>> How do you know that this standard time is not slow compared to your
>>absolute time?
>Standard time is set. Once it is set it becomes the standard for
>background time. So it is meaningless to say that it is slowed
>compared to absolute time (background time).
Ahuh? If the standard clock is moving absolutely (we have no idea
whether it is or not), it certainly cannot be the same time as
"absolute time". The absolute motion of the clock used for standard
time will certainly affect the ticking rate of the clock and the
result should be a discrepancy between it and "absolute time". Should
not absolute time be the time of non-moving frame?
>[...]
>See the explanation for the MMX.
>[...]
>See the explanation for the MMX.
Sorry Ken. Your explanation is seriously lacking, IMO.
Best regards,
Louis Savain
Subject: Re: When will the U.S. finally go metric?
From: pausch@electra.saaf.se (Paul Schlyter)
Date: 28 Oct 1996 12:22:11 +0100
In article <326E72E5.918@flory.mit.edu>,
Peter Mott wrote:
> My opposition to the adaptation of the metric system in the US stems
> from cultural and language-based concerns. Take the unit "mile"
> for example. I can think of a tremendous number of English stories,
> poems, songs, etc. that use this unit, while can think of none that
> use the unit "kilometer." To change to the metric system is to turn
> our backs on this literary history. If need be, I can convert
> one unit to another, but I favor the word "mile" (an elegant word
> that has been in English use for at least 1000 years) over "kilometer"
> (a cumbersome word that has been around only about 100 years).
You can keep your mile, but make it somewhat different in length,
for instance 1.6000 km, or even 1.5000 km, instead of 1.609344 km.
Here in Sweden we also have a "mile" (called "mil" in our language).
Originally it was 36000 (Swedish) feet = 10.689 km, but after Sweden
went metric 100+ years ago, it was changed to 10.000 km. Yes, we
too still use the "mile", both in poetry and literature as well as in
everyday language, although nowadays we do use this "metric mile".
The difference in length between our "metric mile" and our
"traditional mile" is insignificant for these uses. You too can do
the same, with a "mile" adapted to the metric system.
There have been several different miles. In ancient Rome one mile was
1000 "doublesteps" = 1.480 km (the very word "mile" originated from
the Latin "mille", which means "thousand"). The English mile is, as
we know, 1760 years = 1.609344 km. The Swedish mile was 10.689 km but
is now 10.000 km. Then we have the nautical mile = 1.852 km, and the
"geographical mile" = 1/15 degree at the equator = 7.420 km. And
there's even a different English mile: the "London mile" = 1.524 km.
So you can keep your mile, with a somewhat modified length, to be used
in poetry and literature, even though you go metric.
> Secondly, the money required to change everything is astounding.
> Every milling machine, every wrench and drill bit set in every tool
> kit, every calibrated machine tool will need to be changed.
Granted, and one should obviously not throw away all machines at
once. Instead one should, during a transition period, replace them
with new machines having metric capabilities. After some 50 or so
years nobody will be missing this old system of units and the old
machines anymore. Yes, this will have a cost, but different countries
insisting on using different units of measure also costs a lot of
money. In the long run, this cost will be greater.
> Along with these, there are the mental changes that need to be made:
> how many auto mechanics can look at a nut and estimate 9/16", and how
> many can estimate 13 mm? How many Americans know how to dress when
> the guy on the radio says 45 F, and how many know how to dress when
> the radio announcer says 32 C? These mental barriers need to be
> figured into the investment necessary to change to metric.
This is a matter of habit and education. If these mental barriers are
so profound, how do you guys manage to go abroad to metric countries?
Again a transition period is of course needed: young people should be
educated with the new system, and after about one generation very few
will be missing the old system.
Remember that you're not alone with these difficulties. All metric
countries once went through a similar conversion period, requiring
exchange of equipment as well as mental re-training.
> I enjoy seeing Europeans first come to the US, and hear their worries
> about dealing with this backward unit system we have here--gallons,
> miles, pounds. Then after about three weeks, they generally say
> "well, it all fits together a lot better than I expected."
And you will say the same after having lived in a metric country for
a few weeks. It's not THAT hard to re-learn...
--
----------------------------------------------------------------
Paul Schlyter, Swedish Amateur Astronomer's Society (SAAF)
Grev Turegatan 40, S-114 38 Stockholm, SWEDEN
e-mail: pausch@saaf.se psr@home.ausys.se
Subject: Re: probability is relativistic
From: chris@bayes.agric.za (Christopher Gordon)
Date: 28 Oct 1996 11:34:09 GMT
>> Christopher McKinstry (chris@clickable.com) wrote:
>> > I believe probability is relativistic.
>>
>> > Here’s a simple experiment you can try at home to demonstrate
>> > probability changing with speed:
>>
>> > 1) Let "V" the maximum number of digits you can write per second.
>> > 2) In "T" seconds, write down a random number in decimal form.
>>
>> > Now, the maximum number you could have written is "9" repeated VT times.
>> > This is your Reality Radius "RR". The fact you even have one proves
>> > probability behaves relativistically.
>>
>> > Consider, as V decreases, there comes a point at which the only number
>> > you have time to write is "1".
>
If you consider probability to depend on prior information, as many do,
then the situations are not directly comparable as you have different
prior information in each case. ie. Different V. Ofcourse if you dont know how
fast the person is traveling the the best thing you can do is treat speed as a
nuisance parameter and integrate it out, but then you need a
reasonable prior pdf for speed.
--
Christopher Gordon
Remote Sensing, Institute for Soil, Climate and Water,
Private Bag X79, Pretoria 0001, South Africa.
Tel. 27-12 326 4205, Fax 27-12 323 1157,
Email: c_gordon@igkw2.agric.za
Subject: Patrick Fleming; Celtic Crackpot of 1996 (wasThe Sagnac Effect)
From: "David Byrden"
Date: 28 Oct 1996 12:14:24 GMT
Patrick Fleming wrote in article
<54r71f$3l7@nuacht.iol.ie>...
> An explanation of the Sagnac effect based on the Coriolis acceleration
> and the de Broglie/Bohm interpretation of quantum mechanics
Ahh, an Irishman stands up with an "explanation" of the Sagnac effect!
An effect which is perfectly unremarkable, and easily explained through
standard
relativity. An effect that does not NEED to be explained.
This is fascinating, becase only a year ago we had ANOTHER Irishman,
Dr. A. Kelly, telling us "how the Sagnac effect worked" and claiming that
Einstein was
wrong. As I pointed out to him privately, and later to everyone on this
forum, Dr. Kelly
had first misunderstood Relativity, and then he had failed to correctly
analyse the
geometry of the Sagnac experiment itself.
So is this another Celtic Crackpot? What's going on in Ireland that makes
people so desperate to put their names in the physics books? Here goes...
> I wish to put forward an explanation based on the Coriolis effect and
> the de Broglie/Bohm interpretation of quantum mechanics. The Coriolis
> acceleration acts on a body (mass) rotating on a disc, in a
> tangential direction. The Copenhagen interpretation of quantum
> mechanics describes particles as either a particle or a wave depending
> on the mode of observation. The de Broglie/Bohm model states that all
> particles are accompanied by a wave.
I repeat, Sagnac's effect is perfectly well explained by standard
Relativity. Let's see where Mr. Fleming is taking us...
> As points on the circumference of the spinning disc are accelerating
> it is not appropriate to analyse the system in the context of special
> relativity.
Not true! Special relativity does describe acceleration in the
absence of gravity. Don't you know this?
> A particle on the rotating disc is therefore subjected to two
> accelerations, centrifugal (rw^2) and Coriolis (2vw) where:
>
> r = the radius of the disc;
> w = the angular velocity of the frame relative to an inertial
> (constant velocity) frame;
> v = the velocity of the particle relative to the rotating frame.
Stop me if I'm wrong, but don't Coriolis accelerations appear only
if you pretend that the rotating frame is a fixed frame?
> If the tangential velocity of the disc is v1 and the velocity of the
> particle is v then, when the particle and the disc are moving in the
> same direction, the velocity of the particle is v1+v relative to an
> observer on the disc. When the particle and disc are moving in
> opposite directions the velocity of the particle is v1-v. Therefore
> the magnitudes of the Coriolis accelerations acting on the particles
> are different.
YOU GOT YOUR SUBTRACTION AND ADDITION THE WRONG
WAY AROUND!
> In General Relativity clocks tick more slowly the stronger the
> gravitational field. The effect is known as gravitational time
> dilation, as distinct from special relativity time dilation.
> Therefore, the two different accelerations will result in two
> different time dilations, and produce an interference pattern.
JESUS! Even Dr Kelly didn't make THIS stupid mistake!
Dr. Kelly CORRECTLY showed that the relativistic effects
in the Sagnac effect would be extremely small when compared to the
interference effect. You're merely stating WITHOUT ANY FIGURES
that the relativistic effects are the explanation!
> As the effect is produced on all particles, photons, neutrons,
> electrons etc, and since it is mass that acceleration operates on, one
> questions the alleged zero rest mass of the photon. Bass et al (1955)
> and Goldhaber et al (1971) suggested a rest mass for the photon. This
> has been endorsed by Vigier (1996).
This is a digression from what you're supposed to be talking about.
> Chiao et al (1995), in two photon interference experiments, clearly
> brought out the non-local character of the quantum world. A
> consequence of this non-locality (instantaneous influence between
> particles) is an absolute space and time frame.
Oh no it's not.
> It seems therefore
> that the rotating disc and the laboratory are in the same space-time
> frame. Similar effects are seen aboard the disc and in the laboratory.
> It is of interest to note that when the experiment is carried out on
> the surface of the earth (which, of course, can be considered as
> rotating disc at a particular latitude) the same effect is noted.
> Michelson et al (1925) carried out an experiment on the effect of the
> earth’s rotation on the velocity of light. They recorded the
> difference in time taken for the light signals to travel clockwise and
> anti-clockwise. They got a fringe effect on an interferometer,
> indicating a time difference. Saburi et al (1976) sent
> electromagnetic signals around the Earth between standard clock
> stations. The results showed that the signals travelled slower
> eastwards than westwards. One predicts that if the tests were done in
> a north-south direction, with the particles not being affected by the
> Coriolis acceleration, one would not see a time difference or fringe
> effect.
Hmmm. I get a strange sense of deja vu...
> The above analysis, if correct, indicates the non-zero mass of the
> photon and the validity of the de Broglie/Bohm interpretation of
> quantum mechanics.
Analysis??? You wrote only two extremely trivial equations,
and they were BOTH WRONG! The only "analysis" around here is the
one you're overdue for....
> References
>
> Anandan, J. 1981. Sagnac effect in relativistic and non relativistic
> physics. Physical Review D, Vol. 24, No. 2, 338-346
>
> Chiao, R.Y., Kwiat, P.G., Steinberg, A.M., 1995. Quantum non-locality
> in two-photon experiments at Berkeley. Quantum Semiclass.Opt. 7
> 259-278.
>
> Bass, L., Schroedinger, E., 1955, Must the photon mass be zero? Proc.
> Roy. Soc.
> Vol. 232, 1-6.
>
> Goldhaber, A.S., Nieto, M.M., 1971, Terrestrial and Extraterrestrial
> Limits on The Photon Mass, Rev. Mod. Phys.,Vol 43, No. 3, 277-296
>
> Vigier, J.P., 1996, Relativistic interpretation (with non-zero photon
> mass) of the small aether drift velocity detected by Michelson-Morley
> and Miller. (to be published).
>
> Selleri, F., 1996, Noninvariant one -way velocity of light. (to be
> published).
>
> Post, E.J., 1967, Sagnac effect, Rev. Mod. Phys., Vol 39, No. 2.
>
> Saburi, Y., Yamamoto, M., Harada, K., 1976, IEEE Trans, IM25 No. 4,
> 473-477
>
> Michelson, A.,A., 1925, The effect of the earth’s rotation on the
> velocity of light, Astroph. J., Vol. LXI No.3, 137-139.
Oh, very good. If it has a proper list of references, it must be
a valid scientific paper, eh? But tell me why you didn't refer to Dr.
Kelly's
rather amusing papers, since you LIFTED PASSAGES FROM THEM
VERBATIM??
David Byrden
Subject: Re: Collisions
From: checker@netcom.com (Chris Hecker)
Date: Mon, 28 Oct 1996 11:56:12 GMT
mjrust@erols.com (Mike Rust) writes:
>to another, more information is needed. Conservation of kinetic energy (for
>perfectly elastic collision) removes one more unknown, but what is the other
>mathematical relationship? Anyone know?
I'm not sure what you want to do with your collisions. Are you doing
particle physics, or are you trying to write some code to produce an
animation of real world objects colliding, or what? I know absolutely
nothing about particle physics, but if you want to do real world
objects (like a block of wood, a car, or an articulated body or that
sort of thing) colliding, then using conservation laws isn't going to
take you very far, or at least not easily.
I think the equations you want are the following:
1. Poisson's Hypothesis (or a variation of it). This says the outgoing
velocity of the colliding point is proportional to its incoming velocity
by the "coefficient of restitution," which is a scalar that models all
the complicated compression and decompression that happens during a
collision. The equation is:
vo dot n = -e * vi dot n (1)
Where vi and vo are the incoming and outgoing velocities, respectively,
e is the coefficient of restitution (which is 0 for perfectly plastic
collisions, like a lump of clay hitting a table, and 1 for perfectly
elastic collisions, like a superball), and n is the normal vector of
the collision (the table's surface normal for a ball bouncing on a
table).
Since you want to know vo, you need another equation in 2D, or two more
in 3D, since Eq. 1 is a scalar equation. If you want to assume the
collision is frictionless, then your life is easy because this means
there's no tangential impulse, so your components in the tangential
directions (perpendicular to n above) are the same outgoing as they are
incoming.
If you want to model friction, you'll need to do more work, depending on
how realistic you want to be. Search the web for papers by Bhatt and
read Routh's dynamics book (availble from Dover).
If you want to model multiple simultaneous collision points you've got
even more work to do, especially if you want to do friction in this
setting. Look for papers by Baraff and by Trinkle, both on the web.
I hope this helps.
Chris