Subject: Teaching Science Myth (Was: Re: Is glass a solid?)
From: Helge Moulding
Date: Thu, 07 Nov 1996 07:03:22 -0700
Stephen La Joie wrote:
> David Hole wrote:
> > Carl Fink wrote:
> > > TheKit@Life.com (TheKit) wrote:
> > > >How old is thread?
> > > I've been reading this group for over six years, and it's older
> > > than that.
> > You know, perhaps they _should_ start up a new news group on this!
> I don't think this thread is THAT old. I believe it to be less than
> a year old.
The thread itself, maybe. The subject, it's got a grey beard. At least
it does in alt.folklore.urban, alt.folklore.science,
alt.fan.cecil-adams, and possibly sci.misc.
Incidentally, for those in k12.ed.science (that is a newsgroup?), I'm
curious about how people teaching science deal with the distinct
possibility that some of the interesting factoids that they like to use
to liven up lessons are science myths. I prefer it when teachers make it
possible for students to do their own discovery, and it seems to me that
letting them explore the basis for some of these factoids is much more
rewarding than just throwing them out for uncritical consumption.
--
Helge "My glass runneth over..." Moulding
Just another guy
http://www.geocities.com/Athens/1401/ with a weird name
Subject: Re: faster than light travel
From: Eric Kniffin
Date: Thu, 07 Nov 1996 10:10:42 -0800
Wayne Hayes wrote:
>
> In article <327FA357.2302@warwick.net>,
> Eric Kniffin wrote:
> >2-In answer to "We already know that the past can't be changed - because then
> >the present would be different - the question is *why*?", we DON'T know this
> >at all. There was a science-fiction book called "Thrice Upon A Time", where
> >a guy figured ot how to send information back a few minutes in time to
> >himself. Those who received that information acted on it, and changed
> >everything from the moment they received the information onward. They talked
> >about what they called the "Superobserver", who existed outside of
> >time/space/reality. The superobserver would see things happen. Then it
> >would see the information being sent back in time. Then it would see the new
> >reality forming from the moment that the informatin was received.
>
> But this reduces to the same paradox. If, say, the guy gets mugged and
> then sends himself a message back in time saying "don't turn left into
> that dark alley down the street 2 minutes from now", and then gets the
> message, and doesn't turn down the alley, then... who sent it? Certainly
> not the same guy who DIDN'T turn into the alley, because he never turned
> into the alley, and so didn't get mugged, and so didn't send the message.
>
> Well, then, who DID send the message? And what happened to the entire
> universe belonging to the guy who DID send the message? Did it cease
> to exist? When did it cease to exist? The moment he sent the message,
> or the moment (5 minutes previous) that the message is recieved.
>
> Time travel may not be impossible, but if it does occur, it's almost
> certainly not possible to change *anything* in the past --- at least not
> in the same universe that you're doing the travelling in.
Yes, your "can't change anything in the past" scenario is certainly another
possibility. And it takes care of the paradox problems nicely. But I don't
think that anyone can travel to the past and NOT change it. Just being
there, without doing anything, will change things. If you just stand on a
street corner observing, someone will have to step out of the way to avoid
you. So maybe they step into the path of a car. Or maybe someone says "Hi"
to you. Not wanting to get into a conversation that somehow changes that
person, you don't respond. Wondering what makes rude people rude, they get
interested in human behavior. And there's the movie (or Twilight Zone
episode?) where the time traveller steps on a prehistoric butterfly. Which
would have fed some animal. The animal starves, as does the caveman who
would have ate that animal. Maybe you kill a mosquito that was destined to
start a malaria epidemic.
My point is that we don't need to intentionally change things, but I
don't see you it can be avoided. So either time travel is changing things
all the "time", and we can't possibly be aware of them, or there is no time
travel. Personally, I think that it's a fun fantasy. Great for sci-fi.
There have been scientific theories that seemed obvious, but did not actually
work. I think that's what we're dealing with here. Believing in it is a
huge leap of faith.
Subject: Re: Gravity And Electromagnetism
From: kfischer@iglou.com (Ken Fischer)
Date: Thu, 7 Nov 1996 14:10:32 GMT
Allen Meisner (odessey2@ix.netcom.com) wrote:
: In another posting, someone has claimed that gravity is an energy
: carrier and, since energy is quantized, gravity must be quantized. I
: think this is unacceptable.
Unless gravity can be shown by experiments to be
a long range force carrier, I agree.
: Gravity is a potential. You must put energy
: into an object to increase its potential energy. It is this energy that
: is being converted into the Kinectic energy of the object and not
: gravity that is being converted.
But gravitational potential energy is a result of
position, and kinetic energy is not developed until the
object begins falling, reaching the maximum at the closest
approach to the planet, star or moon involved.
In Newtonian gravitation, it is energy developed
by gravity.
: If gravity carried energy, mass would
: have to be continually creating energy, in violation of the law of
: conservation of energy. The question becomes: What is creating the
: potential? GR would imply that mass is itself an energy that curves
: spacetime. If this curvature is finite the energy needed to create the
: curvature is also finite. For this to be possible the radius of
: spacetime must also be finite.
To separate quarks to infinity, the texts say an
infinite amount of energy would be required.
: I find this all very confusing in relation to electromagnetic
: quanta. Since gravitational energy and electrostatic energy cannot be
: "absorbed", how is it that electromagnetic energy can be absorbed?
: There must be a fundamental difference in the way these things operate.
Yes, without a doubt.
: I think it has something to do with gravitational energy and the
: electrostatic energy being potentials and the electromagnetic photons
: being merely a quantity of energy, but I do not know how to explain it
: either mechanically or mathematically.
How something is measured and what model of physics
is used, and the viewpoint of the observer can change how
a quantity can change.
: For example if the photon were a
: curvature of spacetime propagating through spacetime, then particles in
: the path of the photon should move in response to the curvature, and
: the energy of the photon should decrease. This is not observed to
: happen. Could it be that photons only have permissable energy states
: that correspond to maximum and zero energy, while the electrostatic and
: gravitational fields have only one permissable energy state
: corresponding to the maximum energy? This might be possible
: mathematically but it still does not provide a very satisfying answer
: to why particles in the path of a photon can only repsond to the
: curvature in quantized units.
What curvature? Almost 100 percent of the energy
of the photon is an oscillation _NOT_ in the direction of
motion. The major component in the direction is radiation
(light) pressure, which is billions of times less than the
thermal energy of the light.
Ken Fischer
Subject: Re: Gravity And Electromagnetism
From: kfischer@iglou.com (Ken Fischer)
Date: Thu, 7 Nov 1996 13:55:16 GMT
Nathan M. Urban (nurban@csugrad.cs.vt.edu) wrote:
: In article <55r59j$duv@cronkite.amoco.com>, rdholder@amoco.com wrote:
: > I thought that acceleration and deceleration were changes in speed.
: No, they are changes in velocity. Velocity is a vector; speed is its
: magnitude.
But he was questioning a statement that light accelerates
as it is bent when passing the sun's limb.
: > How can the speed of something remain constant as it accelerates?
: Uniform circular motion. Swing a ball around in a circle on the end of
: a string at constant speed. Its velocity vector constantly changes, so
: it accelerates. (Radially inward centripetal acceleration due to the
: tension in the string, to be exact.)
That works fine in Newtonian mechanics, but I don't
think it works for light, and I don't think it is correct
when considering orbits in General Relativity.
I guess you missed the statement that light accelerates.
Ken Fischer
Subject: Teaching programs needed
From: ain@anubis.kbfi.ee (Ain Ainsaar)
Date: 7 Nov 1996 12:12:53 GMT
Hey,
Can anybody tell, how to get teaching programs of physics that can be
appplied at school for demonstrations and practical works, particularly
at the fields where real experiments cannot be carried out, such as
atomic physics, nuclear physics, quantum mechanics, particle physics etc.?
Ain Ainsaar
Subject: Re: Where's the theory? (was: Specialized terminology)
From: turpin@cs.utexas.edu (Russell Turpin)
Date: 7 Nov 1996 09:17:01 -0600
-*-------
In article <3281A817.5A77@nwu.edu>, brian artese wrote:
> Levi-Strauss did a shitload of work collecting all sorts of myths
> disseminated by the several peoples he studied. He would gather in
> front of himself, say, all of the disparate creation-myths. His
> goal was to find among these stories a common structural framework. ...
Yep.
> So in the end, Levi-Strauss claims to have come up with a story that
> acts as a foundational structure which "accounts" for all creation
> stories. ...
Did Levi-Strauss really claim that it was foundational, or merely
that he was identifying commonalities that point to universal
roles these myths play? Even this claim has lots of holes that
need filling, but in either case, I can imagine many more
*sensible* criticisms than:
> ... This presumption of a structural framework, Derrida says,
> is *itself* the "center" that claims to ground and orient all
> creation stories. ...
Perhaps Artese would oblige us with a definition of center that
would help make sense of its use above and below.
> ... Remember that Derrida doesn't "believe" in such a center,
> he's merely pointing out the implications of this kind of
> structural project. ...
If he wants to point "out the implications of this kind of
structural project," he needs to review what (in his view)
Levi-Strauss's projecct was and derive those implications from
that. Artese may not like Perry's summary, but I no more see
what Artese describes (not in any scholarly sense) in "Structure,
Sign, and Play" than what Perry describes. Where is the point by
point review? Where the derivation of implications? In short,
where is the theory?
> ... When he says that this center "is a center that's not a
> center," what he means is that it acts like the hub of a wheel:
> it is the thing that keeps all the disparate stories related
> to one another, *but it is not itself one of those stories*.
As Harter pointed out, it sounds like people are having
difficulty with the notion of a type.
> So when Perry says ... he is, unfortunately, exactly wrong. ...
Before declaring Perry wrong, Artese needs to convince that
Derrida's essay is clear enough (again, where is that theory?)
that Perry *can* be wrong. So far, we have two literary
theorists claiming Derrida does very different things in this
essay, and to someone from another field, it is very easy to read
the essay and think "yes, I can imagine how *that* would happen."
Russell
--
The difference between life and a movie script is that the script has
to make sense. -- Humphrey Bogart
Subject: Re: photosynthesis is green for plants because of plutonium; yellow-green for uranium
From: almenara@nutecnet.com.br (Marcoaurélio Almenara Rodrigues)
Date: Wed, 06 Nov 1996 23:53:42 GMT
Stephen Carino wrote:
>I don't think plutonium has something to do with the green coloration in
>plants. FYI the color that we are observing in plants is due to an array
>of molecules that is collectively called chlorophyll. The reaction center
>of this molecule is consist of a highly conjugated organic molecule which
>is primarily responsible for the color that we see. And that wavelength of
>EM radiation can be closely approximated by the simple particle-in-a-box
>model with the length of the box equal the size and degree of conjugation
>in the molecule..
>And by the way, even though the reaction center is known to be an
>organometallic complex, there has never been a report of plutonium being
>one of the metal atoms. It's usually magnesium, at least, as far as far as
>I can recall.
Mind the expressions, reaction center is a chlorophyll pair where the
photochemistry occurs, and the electrons transport takes place. You
reminded one important issue, plants have an array of chlorophyll
(mostly) responsible for the light absorption. This array is called
Light Harvesting Complex. The excitation energy is transfered by
resonance induction to the special pair, the reaction center. It's
important to note that carotenoids and xantophylls may play an
important role in absorbing light and/or dissipating excess of
excitation. As you told correctly chloropyll has an Mg ion coordinated
with is tetrapyrrol ring, and chlorophyll is bounded by hydrophobic
interactions to proteins. Chlorophyll is green because it has a window
in the green part of the spectrum. Pheophytin, lacks Mg and is a
little bit yellowish. It has no Uranium bound in it, and could not,
otherwise life would be impossible.
Dr. Marcoaurélio Almenara Rodrigues
Rio de Janeiro - RJ - Brasil
e-mail: almenara@nutecnet.com.br
Subject: Re: Action ... and stuff.
From: kunk@perseus.phys.unm.edu ()
Date: 7 Nov 1996 15:08:48 GMT
In article , wrote:
>In article <328139E1.508E@concentric.net>, "J. Matthew Nyman" writes:
>>I have two easy (I hope) questions. Each concerns terminology. The
>>first is the term "action." I have a paper that says:
>>
>>"...where S is the effective action given by
>>
>> S = 1/m^2 INT d^4 x sqrt (-g) (- 1/4 F_uv F^uv + f)"
>>
>>What actually is meant by "action?"
>>
>Action is a functional of the dynamical variables of a system
>(positions and momenta, usually) such that the variation of it yields
>the equations of motion for the system. But, a one sentence
>description doesn't do justice to the subject. I would recommend some
>reading (it is worth it). For example
>
>Goldstein, "Classical Mechanics"
>Landau and Lifshitz, "Mechanics"
>Yourgrau and Mandelstam, "Variational Principles in Dynamics and
>Quantum Theory"
>
>For a very elegant exposition presenting action as the central
>concept of most of physics, you can look up
>
>Amnon Katz, "Classical Mechanics, Quantum Mechanics, Field Theory"
>
There are couple of one sentence descriptions that might stir
your interest.
1. In above statement of dynamics, the bodies follow the path of
least action. This is the fundamental principle.
2. The basic constant of uncertainty, h-bar (or h), has units of action.
Jim
Subject: Re: What is the Cause of Time Dilation?
From: briank@ibm.net (Brian Kennelly)
Date: Thu, 07 Nov 1996 08:25:45 -0700
In article <55q2lh$ceg@sjx-ixn5.ix.netcom.com>,
bjon@ix.netcom.com (Brian D. Jones) wrote:
>steve@unidata.ucar.edu (Steve Emmerson) wrote [in part]:
>
>>In article <55mb90$a1p@dfw-ixnews11.ix.netcom.com>,
>> bjon@ix.netcom.com (Brian Jones) writes:
>
>>> ... And yet the events
>>> themselves obviously can have only a single time between them.
>
>>You seem to believe that absolute time *must* exist? Why?
>
>>> ... Why do all observers' clocks end up
>>> being really and physically different after E-synch is applied? The
>>> only possible cause is their different absolute speeds.
>
>>You seem to believe that absolute motion *must* exist? Why?
>
>>You seem to believe in absolutism. Why? It's not necessary to explain
>>observed phenomenae and adds nothing to our understanding or predictive
>>ability; therefore, it fails the test of Occam's razor. Why do you
>>insist that the concept must be valid? What is your evidence?
>
>>--
>
>>Steve Emmerson steve@unidata.ucar.edu ...!ncar!unidata!steve
>
>Of course an absolute time exists, but that's not to say we have use
>of it.
> §§ ßJ §§
>bjon @ ix. netcom. com
>
Now you are being clear about your assumptions. You begin with absolute time.
Absolute time and lightspeed invariance are incompatible. So your arguments,
based on absolute time, cannot be used to determine what is predicted by SR,
which assumes lightspeed invariance.
I entered this discussion not to convince you that SR is necessarily right,
but to correct your false statements that it was without content. You have
admitted that SR correctly predicts the null result of MMX, and that given
the clock settings of SR, all the normal(?) effects of time dilation, length
contraction and non-linear momentum (or mass increase) follow. Because the
clock settings follow from lightspeed invariance, you have admitted that SR
predicts these things.
So, within the world of SR, it predicts and explains all effects. You reject
the postulate of lightspeed invariance, so you reject SR. Naturally, you are
not satisfied with the explanation. Develop your theory and compare it to SR,
but don't claim that SR is without value because it uses different concepts to
explain things. SR makes the minimum assumptions necessary to explain the
widest possible range of phenomena.
Within your theory you must explain why absolute time is indetectable, and why
moving observers will offset their clocks. This offset is necessary to
explain the null results of first order (to v/c) effects in EM experiments.
Maxwell's equations do not contain 'V', but they correctly describe nature,
showing no v/c effects. If time is absolute, then such effects were expected.
Lorentz introduced the local time (t-vx), but could never work out its
meaning. How do you explain it?
Subject: Re: Teaching Science Myth (Was: Re: Is glass a solid?)
From: hatunen@netcom.com (DaveHatunen)
Date: Thu, 7 Nov 1996 15:27:59 GMT
In article <3281EC2A.6905@slc.unisys.com>,
Helge Moulding wrote:
[...]
>Incidentally, for those in k12.ed.science (that is a newsgroup?), I'm
>curious about how people teaching science deal with the distinct
>possibility that some of the interesting factoids that they like to use
>to liven up lessons are science myths. I prefer it when teachers make it
>possible for students to do their own discovery, and it seems to me that
>letting them explore the basis for some of these factoids is much more
>rewarding than just throwing them out for uncritical consumption.
As one of the few public school science teachers who got a hard-science
degree first (Physics) and then taught, I was appalled at the number of
scientific errors in the general science texts.For the several years I
was teaching I made it a task to check out the various books on
shelves, in adition to the text being used (teachers develop huge
libraries of sample texts).
In the general science text used at Sahuaro High School (Tucson) in
1970 I started red-linign the book, and quit after a few pages when I
realized every page had at least ten small or large errors.
Some of the errors were simplistically misleading, such as continuing
to use the planetary model of the atom, which was discarded by
scientists in the 1920s. Others were downright wrong, such as the
extraordinarily common error that the reason there's a tide on the side
of the earth away from the moon is the centrifugal [sic] force from the
rotation of the earh-moon system.
The tidal error is a pet peeve of mine. I found that it has crept into
almost every general science text published, mostly as a result of
cribbing by authors (who frequently tend to be committees of science
teachers). It has also crept into some encyclopedias. And, most
startling of all, a few years back it was prominently diplayed as the
cause of the far-tide at the Monterey Bay Aquarium, although the last
time I visited that particular display was gone. Maybe they got a clue.
The simple fact is that science teachers simply don't know science.
They go to a College of Education and get their degree in Education.
There is something of a feeling in Colleges of Education that subject
matter isn't as important as Methods of Education.
I thought the year I spent in the University of Arizona College of
Education was one of the silliest experiences I had ever gone through.
Through an odd set of circumstances indirectly involving the Shah of
Iran, I taught full time before I had earned teaching credentials (and
then did my student teaching in the very classroom where I had
previously taught). The experience in the College of Education so
disheartened me that I never did apply for a regular teaching
certificate, although I did substitute for several years.
--
********** DAVE HATUNEN (hatunen@netcom.com) **********
* Daly City California *
* Between San Francisco and South San Francisco *
*******************************************************
Subject: Re: MOST IMPORTANT FOSSIL (A human skull as old as coal!)
From: raven@kaiwan.com (/\/\ )
Date: 7 Nov 1996 07:51:36 -0800
In article <55kug8$p6a@news.ptd.net>, edconrad@prolog.net (Ed Conrad) wrote:
>
>alweiner@presstar.com (Alan Weiner) wrote:
>
>> Big science is big business. If somebody came out with some real
>> info that shattered a major theory, it would get out there faster
>> than the speed of light . . .
>
>to suppress it?
>I most certainly agree!
Oh, you're really being suppressed, Ed.
I guess that explains all those articles I've read by you, but never
could as you were 'suppressed'.
Ed "Come see the censorship inherited in the system! Help! Help!
I'm surpressed!" Conrad.
Ed, you're wasting your life away.
----------------------------
Steve "Chris" Price
Associate Professor of Computational Aesthetics
Amish Chair of Electrical Engineering
University of Ediacara "A fine tradition since 530,000,000 BC"
raven@kaiwan.com
Subject: Re: PHOTON BELT, 3 DAYS OF DARKNESS, COMING SOON
From: kfoster@rainbow.rmii.com (Kurt Foster)
Date: 7 Nov 1996 16:00:45 GMT
photonblt@aol.com wrote:
: (Excerpted from "You Are Becoming a Galactic Human" by
: Virginia Essene and Sheldon Nidle, channeling Sirian Council
: members):
: "The photon belt, a huge torroid shaped object composed
: of photon light particles, was first discovered by your
: scientists in 1961 near the vicinity of the Pleiades by
: satellite instrumentation. The reality is that your solar
: system and the photon belt are moving toward each other [and
: will merge sometime between March, 1995, and the end of
: 1996, or soon thereafter].
:[big cut]
This is raving lunacy. Photons (EM radiation) can't be detected till
arrival. The Pleiades are > 200 light-years away (the star Alcyone is
listed in my Field Guide as 240 ly away). Photons "in the vicinity" of
the Pleiades around 1960 won't arrive here to be detected, till around
the year 2200; whether the Pleiades even exist "now", nature forbids our
knowing till around 2236.
There's a whole SPHERE of photons leaving ANY star -- namely, the
star's light. And, of course, photons move at the speed of light.
Subject: Re: Is glass a solid?
From: Stephen La Joie
Date: Thu, 7 Nov 1996 15:44:00 GMT
Jeffrey Nelson / STILL AGIN' wrote:
>
> On Thu, 31 Oct 1996, Stephen La Joie wrote:
> > What if indeed!
> >
> > I noted that my ol' Chemistry textbook says that glass flows like a liquid,
> > and it was written by a Cal Tech Prof, and now New Scientist
> > backs him up. Maybe it's not a myth. Maybe the only myth here is being
> > spread by the "glass is solid" folk.
>
> Ok, dude, cite the book then, so we can all see. Also, be clear to
> distinguish that he's not talking about molten glass, please.
Well, "dude", I did quote several text, including the one you have
in question, in a usenet post later than the one you quoted. Perhaps
by the time you receive this, it will have appeard on your newsserver.
Subject: Re: What is the Cause of Time Dilation?
From: "Paul B.Andersen"
Date: Thu, 07 Nov 1996 16:07:52 +0100
Brian D. Jones wrote:
>
> An observer has two x-axis clocks that have not yet been started. He
> passes a light source. This source is energized midway of the clocks.
>
> Since the rear clock movesTOWARD the light, and the front clock moves
> AWAY FROM it, the clocks will not be started at (absolutely) the same
> time.
>
> Given that the clocks cannot have the SAME reading at (absolutely) the
> same time, what will their readings be at (absolutely) the same time?
>
> Fill in the blanks:
>
> _________________ _________________
>
> Rear Clock Reading Right Clock Reading
>
> NOTE: You cannot put zero in both places.
In SR there is no such thing as absolute time, so SR can
obviously not give an answer to what the readings of the
clocks are at absolutely the same time.
According to Newton however, we can give an answer which we
know will be wrong for high relative speeds between source
and observer.
As I am sure you know, by rephrasing the question, omitting
the "absolutely" and inserting "in the inertial frame in
which the observer is stationary", SR could give an answer,
and you know what that is.
What is your point?
What is _your_ answer? According to which theory?
SR is a well defined, consistent theory. I am now refering to SR
as the rest of world understands it, not what you say SR should
be, or what you say SR is (whatever that may be), or PR or SRT.
As all consistent theories, SR can only be falsified by showing
that its predictions do not match experimental evidence.
When comparing the predicted values of entities with the
experimental values of the same entities, you obviously have
in both cases to use the same definitions of the entities as
per the theory. When SR predicts a time, you must in the experiment
measure the entity time as defined by SR.
What you are doing, is asserting an absolute space, absolute
velocity and absolute global time. That is your right.
That you are not able to define what those mystical entities
are, or how they could be observed, is your problem.
But when you over and over and over again claim SR to be
wrong because "time" and "velocity" in SR are defined
differently than _your_ mystical entities by the same name,
then you only display faulty logic.
Or have I misinterpreted you?
Do you not claim SR to be wrong?
Paul
Subject: Re: Help: Real-world physics analysis / Turbos vs. Superchargers
From: jayadams@is.dal.ca (Jason Elliot Adams)
Date: 7 Nov 1996 16:10:01 GMT
Jake Russell (jaker@u.washington.edu) wrote:
: Ken Fischer wrote in article ...
: > Jake Russell (jaker@u.washington.edu) wrote:
: > : Hello all Physics buffs!
: > : I was wondering if someone could explain to me in terms of physics why
: a
: > : turbocharger draws less power from an engine than a supercharger does.
: The
: > : turbo is driven by exhaust gasses, where a supercharger is driven by a
: belt
: > : directly off the engine. Does it have something to do with exhaust gas
: > : temperature difference across the turbo?
: >
: > A turbocharger works by changing the vector of the
: > exhaust gas stream, not by direct pressure pumping, where
: > a belt driven or geared supercharger uses engine power.
: > If the exhaust gas was used as a direct pressure
: > pump, then it would not be more efficient, maybe even
: > worse.
: > Pressurized gas jets can impart a great deal of
: > energy without causing very much back pressure when used
: > in a turbine configuration.
: >
: > Ken Fischer
: >
: Thanks for the response.
: I'm starting this thread into the Volkswagen newsgroup for all of us to
: see. We've been wondering why turbo's are more efficient than
: superchargers from a physics explanation. One idea we've thrown around was
: that the temperature of the exhaust gasses has something to do with it
: (This is based on lower temp exhaust gasses having less energy than higher
: temp exhaust gasses.)
: The explanation above is missing something because turbos are known to be
: more efficient than superchargers.
: Comments? Qualifications?
: Go at it, Physics heads and VW enthusiasts! Should be fun an educational
: for us both.
: Jake
This isn't exactly what I think you're looking for but consider this...
If something is attached to the engine crank it will use some of that
crank's power to overcome internal friction and whatnot thus subtracting
some of the power gains. Whereas a turbo has no direct connection to the
crank so it doesn't rob any of the power gain generated.
--
______________________________________________________________________________
Jason Adams
87GTI 8V
Fahrvergnugen Forever!
___
//=========\\ / \
// VV VV \\ )
// VV VV \\ ____/
// VV VV \\ ---====<<<< \\
|| VV VV VV VV || ---====<<< \ \ /(
\\ VV VVV VV // ---==<< \ \__--(
\\ VV VV VV VV // ---====<<< \ \(
\\ VV VV // ---===<<< \
\\=======// \ /\
\ / \
\/ \
______________________________________________________________________________
Subject: Tachyons as force carriers? (was: c as 'speed' of gravity)
From: columbus@pleides.osf.org (Michael Weiss)
Date: 07 Nov 1996 15:21:23 GMT
carlip@dirac.ucdavis.edu (Steve Carlip) makes the interesting point:
The real question is not why gravity propagates at a speed c,
but why light does. I don't know of any simple answer to this.
In modern particle physics, the photon is just one of four
similar particles described by a unified electroweak theory.
(The other three are the W+, W-, and Z bosons.) The photon
happens to move at speed c, but the other three don't. The
technical reason for this is well-understood: [...]
OK, I know that the strong and weak interactions are short range
because their carriers are massive, and conversely the electromagnetic
interaction is long-range because its carrier, the photon, is
massless.
I also know that no tachyons have ever been detected, and if they did
exist, they would give Quantum Field Theory major heartburn. (The FAQ
talks about this.)
So does it even make sense to ask what sort of force tachyons could
carry? In other words, can you take the whole framework that explains
a short-range force as carried by a massive particle (even in a
simplified form, say something like Yukawa's original theory), and
"turn it sideways", getting some kind of force carried by a tachyon?
Or does the framework collapse into a pile of rubble if you try to do
that?
Subject: Re: What is the Cause of Time Dilation?
From: briank@ibm.net (Brian Kennelly)
Date: Thu, 07 Nov 1996 08:12:44 -0700
In article <55r0tn$t91@dfw-ixnews11.ix.netcom.com>,
bjon@ix.netcom.com (Brian D. Jones) wrote:
>briank@ibm.net (Brian Kennelly) wrote [in part]:
>>How do you measure or define this absolute speed? Your argument has now
>>stepped outside SR, and your conclusions cannot be used to criticize SR, only
>>to try to offer an alternative. If you stay within the assumptions of SR,
>>then you cannot carry through your argument.
>
>It exists whether or not I can "define" or "measure" it. If two
>clocks are started by a light source located midway of the clocks, and
>the observer is moving with respect to the light source, the clocks
>cannot be started at the same (absolute) time. They will not be
>absolutely synchronized (as are Newton's clocks -- on paper). They
>will differ absolutely. And there are only (3) things involved:[1]
>the observer's absolute speed V, [2] the distance between the two
>clocks (which can be in terms of a measured value), and [3] light's
>actual (or absolute) speed. No outside observers are there.
>
>In this case, the clocks are started by the light signals, and the
>clocks will differ by exactly DV/c², where D is the observer-measured
>distance between the two clocks, V is the observer's absolute speed,
>and c is light's absolute speed.
>
>
>
> §§ ßJ §§
>bjon @ ix. netcom. com
>
What is the value of V? If this offset is somehow absolutely meaningful, we
should be able to use it to find the value of V.
Only by comparing the clocks to clocks synch'd in another reference frame can
we detect the offset, and each observer will claim that the other has set
their clocks wrong. How do you decide between them? What about a third
observer?
Subject: Re: Teaching Science Myth (Was: Re: Is glass a solid?)
From: Doug Craigen
Date: Thu, 07 Nov 1996 09:27:51 -0600
Helge Moulding wrote:
> Incidentally, for those in k12.ed.science (that is a newsgroup?), I'm
> curious about how people teaching science deal with the distinct
> possibility that some of the interesting factoids that they like to use
> to liven up lessons are science myths. I prefer it when teachers make it
> possible for students to do their own discovery, and it seems to me that
> letting them explore the basis for some of these factoids is much more
> rewarding than just throwing them out for uncritical consumption.
The problem with a good number of such factoids is the inability of
students to replicate the observations themselves - hence the appeals to
believing authorities. The present case of disputing whether glass flow
causes noticeable ripples or base fattening of windows over centuries, is
a good example of this. How could a teacher set up an experiment where
the students could see it happen themselves? A really dedicated teacher
may perform a relatively small scale experiment to test particular
hypotheses. For example, if we assume a widening of 1 mm over 4
centuries, this is 2.5 microns per year. A teacher could set up a pane of
glass for the year and have the students regularly make measurements along
the vertical edge with a micrometer caliper. One could at least then
either come up with a number saying "the degree of pane widening is xxx
microns per year" or "the degree of pane widening is less than xxx microns
per year". A really dedicated teacher might make this a multiyear
project. One could also consider things like sending students out to
record observations on windows of various ages, and to compare their
observations with the history of glass making technology to check for
correlations. However, there is no quick easy way that I can see to allow
students to see the answer for themselves. The best I could propose there
would be tests that allow direct comparison of the mechanical properties
of glass with those of undisputed "solids". Of course, solids flow too,
so this leaves an unresolved semantic issue.
The semanitic issue of what defines a glass is something else again, but
unless handled well would probably put students to sleep.
|++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++|
| Doug Craigen |
| |
| If you think Physics is no laughing matter, think again .... |
| http://cyberspc.mb.ca/~dcc/phys/humor.html |
|++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++|
Subject: Re: When will the U.S. finally go metric?
From: vargenau@aar.alcatel-alsthom.fr (Marc-Etienne Vargenau)
Date: 7 Nov 1996 16:51:20 GMT
In article <55odak$4c6@onramp.arc.nasa.gov>, lamaster@viking.arc.nasa.gov (Hugh LaMaster) writes:
[...]
>fact that road signs are usually still in miles and letter paper
>sizes are still "English". [So what?] What difference does
>it make if a box of cereal says either 16 oz. (454 grams) or
>454 grams (16 oz). Or, 450 gr., 500 gr., or 447.6987 gr.?
One of the problems with the US adopting the SI is that they do not understand it
and often break the rules. I visited the Petrified Forest National Park this summer.
The signs giving the distances inside the park were given in both SI and obsolete
units, and the SI units were even given first. Good. Unfortunately, the sign read :
"16 KM, 10 MI" (instead of "16 km").
You have the same problem in the quoted text. The symbol of the gramme is "g", not
"gr". "gr" is the symbol of the grade. Moreover, there is no dot after the symbol.
Marc-Etienne
========================================================= __
| Marc-Etienne Vargenau | \/
| Alcatel Alsthom Recherche | +--------------+
| Route de Nozay, 91460 MARCOUSSIS, FRANCE | |A L C /\ T E L|
| +33 (0)1 69 63 14 84, vargenau@aar.alcatel-alsthom.fr | +--------------+
========================================================= A L S T H O M
| L'essence des Mathématiques est dans leur liberté. | ================
| Georges Cantor | RECHERCHE
=========================================================
Subject: Re: What is the Cause of Time Dilation?
From: Christopher R Volpe
Date: Thu, 07 Nov 1996 11:43:17 -0500
Brian D. Jones wrote:
>
> throopw@sheol.org (Wayne Throop) wrote [in part]:
>
> >: bjon@ix.netcom.com (Brian Jones)
> >: given any two events, each observer will find a different time between
> >: them. This tells us that their clocks all read differently at these
> >: same two events. And yet the events themselves obviously can have
> >: only a single time between them.
>
> >That doesn't follow. Consider: given any two points on a plane,
> >each observer will find a different delta-x between them. This tells
> >us that their x-coordinate rules all read differently at these
> >two points. And yet the points themselves obviously can have
> >only a single delta-x between them.
>
> >Bjon simply ignores that the two cases are exactly and precisely analogous.
> >He says, yes, there's no absolute direction, but there must be absolute time.
> >Yet he argues for the necessity of "absolute time" via a schema that
> >is obviously vacuous and a non-sequitur.
>
> Nope, Throop, there was no "argument for absolute time." Apparently,
> there's no way (within a finite time) to get the message across to
> you.
Bjon, you JUST GOT THROUGH SAYING that the events themselves "obviously
can have only a single time between them", which is a claim of absolute
time interval, and now you deny that you had argued for absolute time.
Make up your mind.
>
> >The point is, it is SR's model that two events do NOT have
> >"only a single time between them".
>
> >: The invariant interval has no physical meaning, being a mere
> >: mathematical construct.
>
> >This claim is exactly as convincing as a claim that "distance" has
> >no physical meaning, being a mere mathematical construct (x^2+y^2).
> >I've lost count of the number of times I've pointed out to bjon the
> >physical meaning of the interval: it's the number of times a clock will
> >tick in uniform motion between two events.
>
> You're referring not to the invariant interval but to "proper time."
The invariant interval *is* proper time!!! The interval in question is
the space-time interval between two events. Note that in the coordinate
system in which an observer moves inertially between two events in
space-time, the two events take place at the same location (by
construction, each event occurs at location (0,0,0), i.e. the origin, of
the observer's spatial coordinate system). Since they take place at the
same location in this system, the invariant interval has only a temporal
aspect in this system. The entire spacetime interval is a time interval
in this coordinate system, and we call this time interval "proper time".
"Spacetime interval" between two events is synonymous with the proper
time experienced by an observer moving inertially from one event to the
next.
--
Chris Volpe Phone: (518) 387-7766
GE Corporate R&D; Fax: (518) 387-6560
PO Box 8 Email: volpecr@crd.ge.com
Schenectady, NY 12301 Web: http://www.crd.ge.com/~volpecr
.
.
Subject: Anthony Potts, monolingual buffoon...
From: Joseph Edward Nemec
Date: Thu, 07 Nov 1996 12:09:51 -0500
On Thu, 7 Nov 1996, Anthony Potts wrote:
> On Wed, 6 Nov 1996, Joseph Edward Nemec wrote:
>
> > Oxford, but everyone knows what those "automatic degrees" are worth.
>
> That's right, about ten times what your undergraduate degrees are
> worth.
Rubbish. I've spent a considerable amount of time with Oxford and
Cambridge undergrads, and they are definitely not as well educated as
graduates of MIT or Harvard, for example. Most of them here at MIT find
it to be quite a shock at how unprepared they are in many areas. Now,
some of our smaller colleges, yes. But I've also met a large number of
students from your little country's horrible technical schools, and they
are truly poor. I believe you've said so yourself, with typical
arrogance.
> > Oh, and speaking of poorly educated, why don't we continue this
> > conversation
> > in another language. French or German, you choose.
> >
> Si vous voudrais,
^^^^^^^^
If you are attempting to use the present conditional, that should be
"voudriez". Good Lord, your French is terrible.
> je pouves,
^^^^^^
What the hell is this word? What's the matter with the accepted forms of
"pouvoir", not good enough for you? You are actually trying to say to me
that you could speak French if you wanted when you don't even know the
common forms of two of the most basic verbs in the language, "pouvoir"
and "vouloir". Idiot!
> aber ich habe nicht gut Deutsche.
Es steht ja vor der Nase, kleiner.
> Mais, je pense que mon Anglais est suffit.
Ca va sans dire. Mais quant a l'accent ... moi je doute que tu parles
l'anglais de la renne de l'Angleterre. Tu viens, evidement, du Nord, et
les accents la-haut sont affreux. Nous allons voir en Janvier (ou bien
en Mars, je n'ai pas encore decider...)
Alors, moi, ce que je te propose, c'est que tu continues de parler et
ecrire en anglais (le mot "anglais" n'a pas de grande "A" en francais,
petit Antoine, tu te trompes encore) parce que ton francais et vraiment
terrible. C'est un desastre, et c'est aussi la preuve que les
lycees anglais n'apprendent pas les langues etrangeres.
> So, just tell the folks again just what your first university was
> called.
Johns Hopkins University, Baltimore, MD.
I am going to post this risable attempt at foreign languages on your
part to the newsgroups, Anthony. They are too good to keep to myself.
They prove many of my suspicions about you. You are an uncultured,
monolingual, materialistic boor with absolutely no depth.
Funny, you fit the British stereotype of the typical American
much more closely than most Americans...
--------------------------------------
This is a pain which will definitely linger.
-- Brain, after something Pinky did.
Joseph Edward Nemec
Operations Research Center
Room E40-149
Massachusetts Institute of Technology
Cambridge, MA 02139
nemecj@mit.edu
http://web.mit.edu/nemecj/www/
Subject: Re: can value of pi change?
From: jmfbah@aol.com
Date: 7 Nov 1996 14:48:00 GMT
throopw@sheol.org (Wayne Throop) wrote:
:::: In curved geometry, u =|= 2Pi r.
:::: (of course, in general only. u == 2Pi r may happen in curved
geoemtry too.)
::: Would you please tell me
::: what the characters =|= mean in the above equation?
:: schmelze@fermi.wias-berlin.de (Ilja Schmelzer)
:: Not equal. Variants are =/= or != (C-notation).
:Still other variants are \=, ^=, sometimes even ~=,
:or perhaps less confusingly (to some, anyways), <>
:(the last coming from the set)
:
: = equal
: >= greater than or equal
: <= less than or equal
: <> less than or greater than
:
:and used in... hmmm... Pascal, was it? Well, several languages
:in the Algol family anyways. But some math notations have a "box" or
:"diamond" symbol, and so sometimes <> is used to mean that, also.
:
:Or take "^". It can mean (at least, but not restricted to)
:logical not, exponentiation, and logical or.
:
:Ain't equations-in-ascii marvelous?
Actually. They're getting worse. This is the first newsgroup that needs
to use more advanced short-cut terminology for discussions. I find that
my eyes go cross-eyed if I'm trying to figure out what an equation means
when the submitter is writing in MIME-format; I've stopped even trying to
read the words in these messages. I find that Fortran is great for
expressing algebraic notation (like Mati said in another thread, C isn't
his favorite form of cummunication--nor is it mine). But the drawback of
Fortran is that is has no phrase forms for expressing even the simplest
calculus terms. And, then, look at how you denoted previous thread
entries--you used colons--the norm is to use angle brackets; this
obviously was a very bad choice since < and > were an important part of
the subject. And then, I'm still trying to figure out the Venn diagrams
that Baez seems to use. I'm finding that I'm in a country with very
little clues to how to interpret the language. And I've spent over 25
years in the computer business figuring out the rules of a language with
very little context.
The saying that "a picture is worth a thousand words" has tip-toed through
my head almost on a daily basis. Ah, well, now that I've got that pet
peeve off my chest...I firmly believe that this internet exercise will be
producing a communication form that is more precise. And how useful it
would be if you could shove the form through a compiler and get some
computation out it, too!
/BAH
Subject: Re: How Much Math? (Was: Re: How much to invest in such a writer?)
From: matts2@ix.netcom.com (Matt Silberstein)
Date: Thu, 07 Nov 1996 16:41:24 GMT
In talk.origins +@+.+ (G*rd*n) wrote:
[snip]
>
>The discussion about the meaning of _understand_ goes back
>to the idea that some people shouldn't talk about science
>because they don't know the math; therefore they don't
>understand it. This criticism has generally been applied to
>20th-century lit-crit and cult-crit figures. I've never
>seen it applied to Locke, Jefferson, Addison, or Pope, but
>then they were uncritical enthusiasts.
Do you claim that all physics is as much math as Newton? Remember, the
he had just invented/discovered the calculus. Much of that work is
somewhat understandable without all of the math. (But it takes a lot
of work either way.) BTW, do you have any references for how much math
these people had? I suspect that Jefferson had a fair amount.
The bit about their being enthusiasts is misleading. They did not say
Newton war wrong, so they did not need to understand it. And Locke, in
particular, took philosophical/metaphorical implications from the work
that are not in the work. I am glad, however, that he did.
Matt Silberstein
-------------------------------------------------------
Though it would take me a long time to understand the principle,
it was that to be paid for one's joy is to steal.
Mark Helprin
Subject: Re: Is glass a solid? -- how to judge texts, part 2
From: Stephen La Joie
Date: Thu, 7 Nov 1996 17:28:30 GMT
Peter Mott wrote:
>
> Stephen La Joie wrote:
> >
> > Given that there are people in this discussion that have SEEN the effect
> > over time, how can you persist in simply claiming that you're right and
> > they're wrong?
>
> Seen what effect? Creep and/or flow of glass? I never denied it
> existed; on the contrary, I have always pointed out that it did
> occur.
!!!!
So, what is the issue?
[snip]
> >> If glass flows (which it does) defines liquidlike behavior, how does one
> >> reconcile creep behavior of crystaline materials?
> >
> > Different mechanism. Crystaline materials have the long range order and
> > low entropy that make the definition of a solid.
>
> This begs the question. What mechanisms? How these mechanisms
> different
> in crystals compared to glasses? How are these transport mechanisms
> different when coomparing flow to creep? Etc.
> Apparently, you have defined a solid to be a material with a "long range
> order and low entropy." How do you account for liquid crystals, which
> have long range order?
> >>
> >> Kittel can be wrong, too.
> >>
> >> Using viscosity of 10^13 poise is a truly arbitrary definition of a
> >> glass that does not have universal acceptance. A better, more accepted
> >> definition is provided by calorimetry.
> >
> > Yes, Kittel can be wrong. Anyone can be wrong, even you, or I. In such
> > cases, we have to resort to scientific credibility. I am aquainted with
> > Dr. Kittel's credentials. Every solid state prof in physics except one
> > that I know of uses his text. I doubt they would if it was full of glaring
> > errors. While I don't expect you to take my word on the subject on it,
> > I hope that you'd realize that I am not going to agree with you that Kittel
> > is wrong simply because you say "Kittel is can be wrong".
> >
> > And yes, using viscosity to determine what is a glass is aribitrary. But
> > every reference I could find on the subject uses just such an arbitrary
> > distinction. Some even noted that it was arbitrary.
>
> I would argue that when two texts or scientists are at odds, the better
> way to determine who is right is by the content of their arguments and
> by the facts they bring in to support their positions.
>
> I do not want to trash Kittel, because on the whole I find his book
> to be top-rate, and his book is probably the single most important
> contribution to his formidable reputation. But what he wrote on
> glasses is wrong.
Prove it. Am I just suppose to take your word for it? Better yet,
tell Kittel. Maybe he'll include it in the next edition. (Who knows!
Maybe he alread did. My edition is two editions old.)
You can also point out that the Material Science book I quoted
is wrong, as is the McGraw Hill Encyclopidia of physics I didn't
quote.
> Credibility can only go so far. Wrong is wrong, no matter how credible
> the source of error. I pointed out Kittel's errors: 1st, that his
> definition of the glass transition is not universally accepted, but
> that there were better definitions with far higher acceptance amoung
> people that deal with glasses: namely, the peak in the Cp as determined
> by DSC. Other people might use mechanical spectroscopy, at the
> temperature with the maximum loss factor. Both are equally valid,
> both definitions have their weak points, but both are accepted, which
> is not so with the poise definition offered by Kittel. If one
> submitted a paper for publication saying "Tg was determined
> by DSC", the reviews would come back okay, whereas if one submitted
> a paper saying "Tg was determined by where the viscosity reached
> 10^13 poise", the reviewers would not accept this.
>
> Kittel's second and more fundamental error was that he assumes that
> all glassy materials can crystallize, which not true for many glassy
> polymers. Why? Because of the random chemical configuration of polymer
> chain will prevent a regular structure from forming. Atactic polymers
> _can not_ crystallize. Example: atactic polystyrene, a material
> that is probably more common than oxide glasses; it is likely
> that your auto dashboard is made out of it.
Glass polymers is a contradiction of terms. Glasses are made out
of oxides, not plastics.
I've never seen plastics defined as a glass. I've seen stuff that
pointed out that H2O should be a glass, but that it isn't. Plastics?
Never seen it.
But, I'll admit that everything I've done in glass was with metal
oxides.
> >>
> >> All these references do not prove either point one way or the other.
> >
> > What do you require for proof? Either we are all working to the same
> > page or we are not. If conventions in terms in technology are not followed,
> > then we are not even speaking the same language.
>
> You lost me here...proof of what?
You said that my references don't prove either point. I would
like to know your opinion of what is required for "proof."
> Conventions of termonology are indeed the issue. I offered my
> definition
> of a solid, namely "the ability to elastically support a shear stress,
> over
> normal time scales--seconds, days, months." Glass, by this defintion,
> is
> a solid.
And so is water, by surface tention. There are many liquids that
would be solids if we used that as a definition.
> When you use phases such as "vitreous solid" to describe a
> glass, you are tacitly supporting this definition. When you define a
> solid to be "a material with a regular structure with long range order,"
> glass is not a solid, but you will run up against both the scientific
> and common understanding of the word "solid". The choice is yours.
Vitreous solid is a common term used to mean glass. It is an
unfortunate choice of words, because it doesn't refer to a
glass at all.
Every text I've ever seen, and every reference, described a solid
as having long range order and low entropy. Under your definition,
cold molasses is a solid.
> Peter Mott
Subject: Re: What is the Cause of Time Dilation?
From: Christopher R Volpe
Date: Thu, 07 Nov 1996 12:14:32 -0500
Brian D. Jones wrote:
>
> Christopher R Volpe wrote [in part]:
>
> >Asserting that there can be only one time interval between two events is
> >like claiming that there can be only one x interval between two points
> >on a plane.
> >>
>
> >(I think I've made the point clear.)
>
> >--
>
> >Chris Volpe
>
> Slightly wrong analogy, Volpe. In my case, it's the distance between
> the two points in the plane, NOT their x-y-components.
No, in your case it's "distance between two events in spacetime", which
is completely analogous to "x-extent between two points on a plane", in
that neither is absolute.
> But since you
> cannot seem to grasp this, let's go on to the other little example,
> which so far you have managed to ignore.
>
> An observer has two x-axis clocks that have not yet been started. He
> passes a light source. This source is energized midway of the clocks.
>
> Since the rear clock movesTOWARD the light, and the front clock moves
> AWAY FROM it, the clocks will not be started at (absolutely) the same
> time.
SR Has no notion of the concept of "absolutely the same time". It
doesn't exist.
>
> Given that the clocks cannot have the SAME reading at (absolutely) the
> same time, what will their readings be at (absolutely) the same time?
As far as SR is concerned, there is no absolute space or time. It is
perfectly valid to consider the two clocks tto be at rest, and the
source moves from one clock to another. Since it is the source that is
moving, and since the speed of light does not depend on the motion of
the source, the light emitted travels at the same speed to each of the
at-rest clocks. Therefore they are started simultaneously in the frame
in which the clocks are at rest.
>
> Fill in the blanks:
>
> _________________ _________________
>
> Rear Clock Reading Right Clock Reading
>
> NOTE: You cannot put zero in both places.
In the rest frame of the clocks, I sure can. Just because you can't
conceive of an absolute rest frame with respect to which the clock-pair
is moving, doesn't mean that no such frame exists.
--
Chris Volpe Phone: (518) 387-7766
GE Corporate R&D; Fax: (518) 387-6560
PO Box 8 Email: volpecr@crd.ge.com
Schenectady, NY 12301 Web: http://www.crd.ge.com/~volpecr
.
.
Subject: Re: x litres gas = 1 cu metre?
From: Alan \"Uncle Al\" Schwartz
Date: 7 Nov 1996 17:34:52 GMT
kkostenb@ccs.carleton.ca (kkostenb) wrote:
>
>Hello,
>
>I'm having trouble finding out how many litres of gasoline
>fit into one cubic metre (or gallons/cu feet). I'd need the information,
>but no little physics. Do you know the answer?
>
>Thank you!
>Klaus Kostenbauer
Ah, guy, are you really sullying the corridors of higher education?
A cubic meter is 1000 liters is a 1,000,000 cubic centimeters. The
identity of the filling, from vacuum to depleted uranium, is irrelevant.
(Neutronium might require a relativistic correction for the gravity.)
Conversion tables for English measures are not uncommon, just unwelcome.
--
Alan "Uncle Al" Schwartz
UncleAl0@ix.netcom.com ("zero" before @)
http://www.ultra.net.au/~wisby/uncleal.htm (lots of + new)
(Toxic URL! Unsafe for children, Democrats, and most mammals)
"Quis custodiet ipsos custodes?" The Net!
Subject: Re: How Much Math? (Was: Re: How much to invest in such a writer?)
From: +@+.+ (G*rd*n)
Date: 7 Nov 1996 12:47:38 -0500
+@+.+ (G*rd*n) wrote:
| >...
| >The discussion about the meaning of _understand_ goes back
| >to the idea that some people shouldn't talk about science
| >because they don't know the math; therefore they don't
| >understand it. This criticism has generally been applied to
| >20th-century lit-crit and cult-crit figures. I've never
| >seen it applied to Locke, Jefferson, Addison, or Pope, but
| >then they were uncritical enthusiasts.
matts2@ix.netcom.com (Matt Silberstein):
| Do you claim that all physics is as much math as Newton?
No, not at all. I just posted that famous remark about
QM. Certainly Ptolmaic and Newtonian mechanics are more
available to our pre-mathematical intuitions than QM, with
the Relativities being somewhere in between. Going by
what people in the business say, anyway.
| Remember, the
| he had just invented/discovered the calculus. Much of that work is
| somewhat understandable without all of the math. (But it takes a lot
| of work either way.) BTW, do you have any references for how much math
| these people had? I suspect that Jefferson had a fair amount.
Jefferson might have done some Calculus; the point here is
that nobody has checked up on him. Although perhaps I could
get a flame war going by asserting that Jefferson was not
only a racist and a slavemaster, but a math-deficient
ignoramus. I think I'll pass, though. If Locke, Addison,
or Pope studied Calculus I have never heard about it.
| The bit about their being enthusiasts is misleading. They did not say
| Newton war wrong, so they did not need to understand it.
They said he was right, which is the same order of
declaration as saying he was wrong. For example, Pope:
God said, Let Newton be; and all was light.
If Pope is allowed to say that without knowing his Calculus,
then moggin is allowed to say Newton was wrong, or even the
apotheosis of darkness and evil.
| And Locke, in
| particular, took philosophical/metaphorical implications from the work
| that are not in the work. I am glad, however, that he did.
What's sauce for the goose is sauce for the gander. Were I
not a vegetarian, I would try Patak's Lime Pickle Extra Hot
on both. _Cautiously_.
--
}"{ G*rd*n }"{ gcf @ panix.com }"{
Subject: Re: What is the Cause of Time Dilation?
From: Christopher R Volpe
Date: Thu, 07 Nov 1996 12:21:05 -0500
Brian Jones wrote:
>
> Christopher R Volpe wrote[in part]:
>
> >Brian Jones wrote:
> >>
> >> briank@ibm.net (Brian Kennelly) wrote[in part]:
> >>
> >> > Physics provides no
> >> >operational definition for "absolute" or "relative" synchonization without
> >> >defining those terms.
> >>
> >> Einstein long ago did this very thing. He said that "absolute time"
> >> means simply that all observers find the same time interval for two
> >> events.
>
> >Correct. THat is what absolute time means. Just like the word "unicorn"
> >means "horse with a lion's tail and a horn in the middle of its
> >forehead". However, the fact that these words have meaning doesn't mean
> >they describe reality.
>
>
> The dude did not ask for reality, but only for an operational def. of
> absolute time.
Right. You have given a definition, but not an OPERATIONAL definition.
An operational definition is a procedure that you are physically able to
follow in any inertial lab (and by "physically able to follow", I mean
without being magically "given" things like clocks presumed to be at
absolute rest) to determine whether two events occur at the "same time",
independent of inertial frame. I.e. you have to be able to say something
along the lines of "Events A and B are simultaneous if this-and-that
happens when I do such-and-such", and have the answer be independent of
the inertial frame in which the procedure is carried out.
--
Chris Volpe Phone: (518) 387-7766
GE Corporate R&D; Fax: (518) 387-6560
PO Box 8 Email: volpecr@crd.ge.com
Schenectady, NY 12301 Web: http://www.crd.ge.com/~volpecr
.
.