🚀 go-pugleaf

On Fri, 18 Jan 2008 00:57:17 -0800 (PST), Pentcho Valev
<pvalev@yahoo.com> wrote:

>On Jan 16, 5:37�am, Eric Baird wrote:
>> On Tue, 25 Dec 2007 02:29:16 -0800 (PST), Pentcho Valev
>>
>> <pva...@yahoo.com> wrote:
>> >One can never know how exactly silly Einsteinans draw their
>> >conclusions but at least one can guess. So this Eric Baird may have
>> >decided to get rid of special relativity after reading the following
>> >two texts:
>>
>> >http://www.pitt.edu/~jdnorton/Goodies/rel_of_sim/index.html
>> >John Norton: "But an emission theory is precluded in special
>> >relativity by the part of the light postulate that asserts that the
>> >velocity of light is independent of the velocity of the emitter."
>>
>> >http://press.princeton.edu/chapters/i6272.html
>> >John Stachel: "Not only is the theory [of relativity] COMPATIBLE WITH
>> >AN EMISSION THEORY OF RADIATION, since it implies that the velocity of
>> >light is always the same relative to its source; the theory also
>> >requires that radiation transfer mass between an emitter and an
>> >absorber, reinforcing Einstein's light quantum hypothesis that
>> >radiation manifests a particulate structure under certain
>> >circumstances."
>>
>> >Eric Baird's possible conclusion: "Master John Norton clearly says the
>> >emission theory is incompatible with special relativity whereas Master
>> >John Stachel says it is compatible with "the theory". The only
>> >solution to the problem is to abandon special relativity and continue
>> >to worship, as fiercely as possible, general relativity."
>>
>> >Pentcho Valev
>> >pva...@yahoo.com
>>
>> No ... since my name's being brought up here, I should point out that
>> I'm not aware of having been influenced by either Stachel or Norton.
>> The line of reasoning above doesn't really represent my position.
>
>Here is your "position":
>
>http://arxiv.org/html/gr-qc/9807084
>Eric Baird: "4.1. Local lightspeed constancy. If two objects with
>relative velocity v are separated by an effective gravitational
>gradient with an associated terminal velocity v, then light passed
>between the objects and riding this gravitational gradient can be
>emitted at c relative to the emitter and received at c relative to the
>absorber, and can have a range of intermediate velocities in the
>intervening region that are dictated by the local gravitational
>properties encountered along its path. This provides a gravitational
>mechanism for local lightspeed constancy that is essentially
>Einstein's amended 1911 description ("The principle of the constancy
>of the velocity of light holds good according to this theory in a
>different form from that which usually underlies the ordinary theory
>of relativity." [20] ), when motion shifts are considered as
>gravitational effects (NB: in this model, the equivalent gravitational
>terminal velocity between two events is route-dependent rather than
>absolute). If we attempted to measure an intermediate speed in this
>region by introducing a physical probe with a new velocity, the
>presence of the probe would alter the surrounding geometry so that we
>would again get a local measurement of c relative to the probe. DMS
>models include a feature of quantum mechanics in that the act of
>measurement cannot be isolated from the system that is being
>examined."

No, Pentcho, you don't get to define what my position is, only =I= get
to do that! :)

Papers tend to explore arguments or lay out facts rather than defining
personal positions. gr-qc/9807084 was a paper exploring a possible
mechanism for local lightspeed regulation. It extended the usual idea
of observerspace physics, and explored what would happen if we used an
additional equivalence principle based on the idea that it's difficult
for observers to differentiate between the effects associated with
gravitational shifts and those associated with velocity shifts,
without applying a certain degree of interpretation.

Of course, we /know/ that the two sets of effects are fundamentally
different in origin, but if we were less knowledgable and just treated
the two effects as they /appear/, it'd be logical to try to integrate
them into a single description. 
The result of that crazy, wrong-headed idea would be that we'd then
expect moving material to drag light (Fizeau), and the equatorial
regions of rotating bodies to attract more strongly at their receding
edge than at their approaching edge (frame-dragging, GR, Mach's
principle), and we'd end up with an acoustic metric rather than a
Minkoswki metric (acoustic metrics are currently being studied by some
of the "quantum gravity" guys as potential toy models of how the new
physics might operate).
So although the idea is obviously "crazy", it generates some good
results, quite efficiently, from fundamental principles. And it
generates local c-constancy. It also bypasses the usual proofs about
the inevitability of the SR equations, without breaking the principle
of relativity. 

Now, gr-qc/9807084 did have some problems, which were addressed in a
later piece, also on LANL, called, suitably enough, "Problems with "SR
without GR" ... " LANL shunted it into the "physics" category, so you
probably didn't see it:
  http://arxiv.org/abs/physics/0102082
:ABSTRACT:
: Einstein's goal of producing an advanced gravitational model 
: that was independent of special relativity's "non-gravitational" 
: derivations has arguably still not been achieved. The author 
: produced a paper in 1998 outlining a possible method of attack 
: on the problem based on shift equivalence principles ("Doppler 
: mass shift"). Some problems with this paper have since come to 
: light. We list some further developments, some papers not cited 
: in gr-qc/9807084, some experimental results missed by the author, 
: and identify a problem with the paper's approach to aberration 
: effects.


I'd already worked out that, with a range of different propagation
models, if you calculate the apparent aberration in angle of a moving
object's fieldlines, and apply that geometry to the object's apparent
gravitational field, then use that apparent field component to
calculate a gravitational shift, a crude calculation seems to generate
the same order-of-magnitude shift as the conventional motion-shift
effects. This suggested that either the total motion shift was twice
as strong as expected (which didn't seem credible), or that
motion-shift and gravitational-shift arguments could be
interchangeable in the context of a model in which relative motion
between objects is associated with a matching spacetime curvature. The
object's own motion and momentum characteristics then effectively get
written into the footprint that it makes on the metric.  

What I hadn't quite gotten to grips with in gr-qc/9807084 was why the
calculated effects associated with the aberrated /environment/ seemed
to act in the opposite direction. Later I realised that this wasn't a
bug but a feature: In this sort of model, it's the mechanism that
allows Newton's laws to operate. The apparent flat-spacetime
background for inertially-moving objects is maintained by two
different curvature mechanisms acting in opposition.
In a velocity-curved model, an object moving through a distant
homogenous environement at fixed speed should see the environment to
be more concentrated in front of it, and if the gravitational sources
of the background stars appear to coincide with their visible
positons, you /might/ expect this distortion to be associated with a
further forward acceleration ... but the "gravitational dragging"
effect compensates. The larger number of approaching blueshifted stars
that the object sees in front each appears to have a reduced pull, and
the smaller number of receding redshifted stars seen behind each seem
to have an increased pull (to match the degree of shift). If the
initial distribution is even, then the two effects cancel. If the
initial distribution of mass isn't even (say, if there's a planet
nearby), the two effects no longer cancel, and the "moving" planet is
associated with a measurable gravitomagnetic effect.


My "take" on these problems evolved a bit since '98. 
The book (late 2007) represents my best effort to date to try to
explain some of these issues, and represents my current opinions. 

The luxury of having nearly 400 pages to present a set of arguments is
that you have the space to go back to first principles and work up a
set of disparate arguments from scratch, and then pull them all
together. You can't do that in a ten-page journal paper.


The 2007 book is now searchable online using Google Booksearch 

 http://books.google.co.uk/books?q=0955706807&btnG=Search+Books 



>Even zombies in Einstein criminal cult would find your "position" too
>silly.

:)

To steal the famous Pauli quote, the fact that the idea is "crazy"
isn't in doubt, the question is, whether it's crazy /enough/ to also
have a chance of being correct. 

The hallmark of a truly great science idea is that when you first see
it it looks utterly, obviously, insane, and totally unworkable ... 
... and yet it somehow works nevertheless.

The Earth goes around the Sun? Preposterous! The people would all fly
off! Diseases caused by little invisible single cells? Ludicrous!


Do you want to know the secret of navigating a professionally-designed
labyrinth? If the designer is really good, at each junction of the
labyrinth there will be one or more paths that look obvious or
reasonable, and one other path that looks so obviously /wrong/ that
you dismiss it immediately. That path is the correct one. Deliberately
take the "dumb" path at each junction and you'll be able to walk
straight out of the maze without even thinking. 

That's what blue-sky theoretical physics is like. 

You have to assume that all the good, straightforward, sane-looking
ideas have already been taken by other people. For a reasonably
straightforward idea to have been missed by all those other clever
people, it has to be something that looks /so/ wrong that everyone
else has ignored it, or instinctively dismissed the thing so
reflexively that perhaps they never even consciously registered the
idea as being a possibility. 

That's your potential solution. So, track down the ideas that nobody's
bothered disproving, because they're clearly too dumb to work, and
derive an objective, fair-minded disproof of each one. When you find
one that, inexplicably, seems to resist all attempts to disprove it
without resorting to cheating, then that's your candidate theory. 


> Stop writing books! Withdraw books already published!

heh. :)

=Erk= (Eric Baird)
 www.relativitybook.com