Re: Yes, Paul?Re: Equivalence my ass! Re: Well, Hobba? Re: A. Newtonian Invariance vs SR-cult fraud and corruption (Rev B)

From: Bill Hobba (bhobba_at_rubbish.net.au)
Date: 10/24/04 

Date: Sun, 24 Oct 2004 22:57:30 GMT

"Bill Hobba" <bhobba@rubbish.net.au> wrote in message
news:o9Hed.37174$5O5.17791@news-server.bigpond.net.au...
>
> "Mike" <eleatis@yahoo.gr> wrote in message
> news:9c1b39be.0410231519.7062b3e0@posting.google.com...
> > "Bill Hobba" <bhobba@rubbish.net.au> wrote in message
> news:<dnhed.35776$5O5.2466@news-server.bigpond.net.au>...
> > > "eleaticus" <eleaticus@bellsouth.net> wrote in message
> > > news:aBfed.43875$pi7.23026@bignews4.bellsouth.net...
> > > >
> > > > "Paul Draper" <pdraper@yahoo.com> wrote in message
> > > > news:74768d2d.0410221336.6341411@posting.google.com...
> > > > > daryl@atc-nycorp.com (Daryl McCullough) wrote in message
> > > > news:<clap4r01dmn@drn.newsguy.com>...
> > > >
> > > > > > So the conclusion of your demonstration is observably false.
> > > > >
> > > > > There's another demonstration that shows this beautifully. You and
a
> > > > > buddy go to the playground with a basketball and get on one of
those
> > > > > rotatable turntables that the kids spin on until they get
nauseous.
> > > > > Once you've gotten up to speed, you and your buddy stand at
opposite
> > > > > points on the perimeter of the turntable and toss the ball to each
> > > > > other. The path of a thrown ball in this rotating frame is
something
> > > > > that has to be seen to be believed! With practice, you can throw
the
> > > > > ball directly across the turntable and catch it yourself!
> > > >
> > > > I told y'all how to do it, how to show that the relative velocity
wrt
> to
> > > an
> > > > accelerating system has nothing to do with the question of whether
the
> > > > inertial obect actually travels a straight line as defined by the
> > > continual
> > > > comparison of 'milestone' coordinates: B'-A' = C'-B'.
> > >
> > > Get real. When the turntable is not rotating push the ball and
> (neglecting
> > > air resistance and gravity) it travels in a straight line relative to
> you
> > > and a Cartesian coordinate system say painted on the turntable and a
> pole
> > > where you are standing - experimental fact. Spin the turntable and
> relative
> > > to exactly the same coordinate system the ball no longer travels at
> constant
> > > velocity in a straight line - again experimental fact. Thus how the
> ball
> > > behaves when it is thrown are different. The whole issue boils down
to
> what
> > > one counts as a law of physics - it is obvious that free particles no
> longer
> > > travel at constant velocity (but see my other comments below) so if
you
> > > count that as a law of physics (and most would - it is Newton's first
> law of
> > > motion) then the laws of physics are different. However what Einstein
> says
> > > with the principle of general invariance is that is not how we should
> > > express laws of nature - we should write then in covariant form so
they
> are
> > > the same in any coordinate system. Thus you either say - Newton's
first
> law
> > > of motion is not a valid law because it is not expressed conveniently
or
> you
> > > say that the laws motion are different in accelerated frames. Take
your
> > > pick - each is ok by me - although I generally opt for the second one.
> > >
> > > But care is also required - Newton's first law of motion is really
> > > circular - it says a free particle moves at constant velocity unless
> acted
> > > on by a force. We release the ball - we find nothing else in the
system
> > > acting on it (remember we are neglecting air resistance and gravity)
so
> > > according to our intuitive idea of free particle it is not acted on by
a
> > > force so should move at constant velocity - so we conclude the frame
is
> not
> > > inertial. Or we can say - hey it is not moving at constant velocity
so
> is
> > > not free thus Newton's first law still holds. Newton's first law is
> seen to
> > > be rather vacuous (force free means moving at constant velocity - so
> what do
> > > we count as force free?) - it is in fact circular so it is quite
> reasonable
> > > to say it is not a law worth saving. We would be better of basing our
> > > definition of inertial frame and formulation of the laws of motion on
> the
> > > principle of equivalence and the symmetries of an inerital frame -
that
> way
> > > we never run into problems. But it is a bit sad we need such an
> advanced
> > > theory to get around these issues - which is why I generally opt for
the
> > > second option and say the laws of physics are not the same in
> accelerated
> > > frames. However I am happy with either view as long as the person
makes
> it
> > > clear which view they are advocating and use it consistently. In fact
> if
> > > Newton's laws were scrapped in teaching mechanics (see
> > > http://www.eftaylor.com/pub/FmaAJPguest5.pdf - ie it was all based on
> the
> > > PLA) and we define an inertial frame by its symmetry properties then
> IMHO le
> > > ss problems would arise and we would all be better off. The laws of
> physics
> > > would be the same in all frames right from the outset - conservation
of
> > > momentum, energy etc would be seen for what they are - simply a
> reflection
> > > of the underlying symmetry of an inertial frame.
> > >
> > > Bill
> > >
> >
> > You do not know what you're talking about. Now I am convinced. So is
> > your prof. Taylor. Hidding the problem does not eliminate it.
>
> Taylor is a well respected physicist, world renewed for his textbooks on
> relativity written with Wheeler - an acknowledged master of relativity.
If
> Wheeler and Taylor do not know what he is talking about no one does.
>
> >
> > Tell me something. How would you teach the LPA?
> >
>
> What is the LPA? Do you mean PLA - the principle of least action.?
>
> > as a 'a priori truth',
>
> The only 'a priori truth' is logic - and even there debate exists.
>
> > as an empirical proposition or as a mathematical model in a
> > constructivism sense.
>
> I would simply point out, as Taylor does, that an alternative formulation
of
> QM is Feymans sum over histories approach. The little arrow that turns in
> this explanation cancels all paths except those where the exponent s in
e^is
> does not vary - this s is in fact the Lagrangeian.

Dear oh dear - should be more careful. S is of course the action from which
one derives the lagrangian density.

Sorry
Bill

Another method as
> espoused in Landau - Mechanics and Classical Mechanics, Quantum Mechanics
> and Field Theory by Amnon Katz is to take the PLA as foundational and
> develop mechanics from it. QM is seen to result from what is known as
> saddle point integration (page 40-41 of the reference byAmnon Katz). In
> this formulation one can introduce the powerful Noether theorem. But this
is
> a problem for educators and choosing a style suitable for the kinds of
> students they have, their background and interests. I am simply noting
the
> circularity one has with Newton's first law disappears in such an
approach.
>
> > Is it a Platonic, Formalistic or Constructivist
> > approach to physics?
>
> This is physics not mathematics - so the answer is none of the above or
more
> specifically who gives a ****. I leave such to the person who writes the
> book. In Taylor's case his style has been described as 'pedagogically
> sound' but informal and 'pokey'. As Feynman says in his lectures there is
> no standard answer to such questions - one chooses the teaching style
> depending on the material - just like he choose different styles in his
> famous lectures.
>
> >
> > Do you think the PLA would make sense in lieu of Newton's Laws?
> >
>
> Do you ever ensure brain is engaged before opening mouth or do you always
> sprout off about what you obviously know nothing about? Their is a well
> known mathematical theorem saying the two approaches are equivalent. The
> Lagrnagian approach is better because it generalizes beyond classical
> mechanics, has a closer relationship to QM, and allows wielding of
Noethers
> powerful theorem.
>
> > Do you
> > want to taylor physics teachings so they can be understood by the
> > average moron who pays for education? Do you think such approach is
> > for the benefit of society?
>
> I do not think in such terms. I think in terms of trying it out on a
small
> scale and seeing what happens - which is exactly what is occurring. What
we
> need in education is less perception on what must be done and more choice
> for the student. Teaching physics by the PLA as advocated by Taylor is
part
> of such a process. If it paves successful it will expand - if not it will
> go the way of the dinosaurs and students will wait for graduate school be
> exposed to it.
>
> >
> > Are you trying to set the foundations for the next round of dark ages?
> > Don't you feel any shame at all?
> >
>
> It is obvious you understand very little about physics at all.
>
> Bill
>
> >
> > Mike
>
>

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