Natural Science Forum / Physics / General Physics / July 2008

No. I just find ordinary anti-relativists like Pencho, Androcles,
Spaceman boring and find Baird interesting as he is perhaps
the only one who publishes an anti-relativity book in the public.
Since I'm not a supreme relativist like Tom Roberts. I need
assistance in analyzing it. Don't worry. You don't have to buy
the book. By debunking what he says above. You shatter
all his theoretical reasonings in the book which is based on
the above main theme. Find the fatal flaw and your cut him
off and the crackpot, if he is one, is debunked.

If you will notice, all roads lead to quantum gravity. If the
initial assumptions is incorrect, we may not arrive at QQ
unless we got the foundations right. I just wonder if there
is really a way to re model GR without SR which he said
is a flaw rght from the start. What do you think? Give me
penetrating counter insights and reasonings and i'm outta
here. Just need multidisciplinary scrutiny from relativist
veterans.

Danny

Baird main counterarguments from his website mentioning
what went wrong in the development of relativity (he is
going for the kill):

GR1915 is meant to be a superset of special relativity,
with the equations and relationships of SR built into
the theory as a limiting case. Although special
relativity made a few simplifying assumptions that
weren't really appropriate for a general theory of
relativity (such as the equivalence of inertial mass
without gravitational mass, and the allowance of
arbitrarily high concentrations of kinetic energy
without curvature), GR1915 nevertheless assumes that
the relationships that SR obtained by doing thi s were
the correct ones, and that they have to carry over into
our shiny new "curved spacetime" theory.

When Einstein was designing his general theory, he was
trying something very ambitious. As someone who wasn't
a professional mathematician, he was trying to produce
a curvature based solution where the mathematical
"greats" before him had failed. He had the advantage
over Nineteenth-Century researchers of having realised
that gravity had to bend both space and time, but he'd
published that result in 1911, and now he was racing to
produce a general theory before someone else beat him
to it. He was familiar w ith special relativity, he
trusted it, ,rid by declaring that general relativity
had to reduce to it, he managed to narrow the options
for how his new theory should function without having
to start over completely from scratch.

Einstein doesn't seem to have demonstrated that general
theories must reduce to special relativity, and doesn't
seem to have been able to rederive SR's equations of
motion in the context of a curved-spacetime model. But
by deciding that his general theory would reduce to SR
as a matter of design, he made his job slightly easier.

"flatness" in classical field theory at small scales

The geometrical argument for GR's reduction to SR goes
something like this: general relativity describes the
shape of the metric as curved, but as we zoom in to
examine smaller regions of spacetime, larger-scale
curvatures become more difficult to notice. Eventually,
if we zoom in arbitrarily far, we find ourselves
looking at a section of metric that is arbitrarily
flat, and we can then argue that, in this small region
that is effectively curvature-free, relativistic
geometry must conform to the flat-spacet ime
relationships of special relativity.

Fair enough. But it doesn't follow from this that a
general theory of relativity is compelled to reduce to
the physics of SR, unless we can also show that
curvature isn't an intrinsic feature of particles and
their interactions ... it ignores the possibility that
perhaps physics is curvature. If we zoom in so far that
curvature effects no longer exist in our selected
region, then this might just mean that we've zoomed in
too far, and are now studying a region in which no
meaningful physics is taking place.

The idea of- "intrinsic curvature" would spoil the case
for SR being inevitable as physical law. If we were to
believe that the massenergy of particles warps
spacetime, and that relative motion is expressed as
further warpage of spacetime, then by zooming in so far
that there is significant curvature in our field of
view, our "flat" region would seem to be defined by an
absense of any interesting physics The region wouldn't
contain any particles with significant relative motion,
or any associated gravitomag netic effects, or
particles with any relativie motion at all. In fact, it
wouldn't contain any particles, period. The limiting
case where SR would be geometrically valid would then
be the case where there is actually no physics to
describe, and as soon as we started including real
particles with real energies and rnotion, our "proof"
of a reduction to special relativity would fail. ,

We'd have nothing happening, and nobody to watch it not
happening. We'd also not have compelling reason to
insist that the principle of relativity had any reason
to apply to the "empty" region, because there wouldn't
be anything concrete to apply the PoR  to: if the
principle hypothetically didn't hold in the empty
region for observers that didn't exist, we'd probably
be none the wiser ... there'd be nothing unusual to see
and nobody to notice, and no. one to file a complaint.
This would seem to be null phy sics.

So, to say that we know that it's a geometrical
requirement for general theories to reduce to the
physics of SR, for real objects, is equivalent to
saying that we know that gravitomagnetism and
particulate effects and energy don't warp spacetime in
a significant way, and don't play an essential role in
the physical interactions between bodies. It's a
rejection of geometrodynamic principles. The special
theory doesn't seem to emerge from curved-spacetime
geometry as physics unless we've already convinced our
selves that the SR concept of "the physics of flat
spacetime" is valid. The background arena in which
inertial physics is enacted may well be flat, but the
actions themselves need not be - the flatness of the
background "stage scenery" doesn't have to apply to the
actors on the stage.

It may well be that all physics is geometry. It does
not follow that all geometry is physics.

WHAT'S WRONG WITH SR

SR and Observerspace

Explanations of special relativity often emphasise the
importance of "observers" and "observations", and this
can give the impression that Einstein's special theory
is a literal Observerspace theory - that is, that it
deals directly with what observers at particular
locations should experience. This seems to make a
strong case for the idea that the special theory's
physical predictions have to apply if the principle of
relativity is correct.

But this impression wouldn't be entirely accurate. By
convention, a perfect observer is Usually supposed to
be someone or something that records the experiences
that they're presented with, literally, without
extrapolation or bias - they try to report their
experiences objectively without imposing their own
personal belief systems or interpretations onto the
data that they collect. An "observationalist" theory
will tend to say that what we see to be happening is,
for us, what is happening, and if we define our
"observers" broadly enough to include solid inanimate
bodies and atoms, then our resulting theory of how
these objects "see and feel" each other should then
tell us something useful about the actual physics of
how these bodies interact with each other.

But, as James Terrell eventually pointed out (in 1959)
this doesn't correspond to the behaviour of "observers"
under special relativity. Einstein's special theory
insists that inertial observers can extrapolate their
own locally-constant speed of light outwards throughout
the surrounding region, and can also treat the velocity
of light as a global constant, and their observations"
are predicted, interpreted and reported in the context
of these new beliefs. This reinvention of the act of
observation, incorpo rating the assumption of flat
spacetime, restricts our relativistic options to the
equations of special relativity. The theory does then
go on to make specific physical predictions for the
effects that should be directly visible according to
the theory ... but we have to remember that what an SR
observer is supposed to observe isn't necessarily what
the theory predicts they should actually be seeing.

"non-SR" observerspace approaches

Could we try to build a more literal observerspace
model than SR? If we try, we immediately run into some
odd behaviour. For instance, if we said that the rate
of timeflow of an object (for a given observer) was the
rate that that observer would see the object to have,
then a circle of "stationary" observers surrounding a
"moving" object would report different ', observe&
values for the object's rate of timeflow depending on
their viewing angle - an observer in front of the
object would see it ageing more q uickly, and an
observer behind it would see it ageing more slowly. We
wouldn't be able to use a single value for the object's
11 observed rate of timeflow" according to observers in
the same inertial frame, and our more abstract SR logic
to do with collections of "observers" and "frames"
wouldn't work.

If we took this "seen" behaviour literally, we'd have
to allow an object's apparent rate of timeflow, to be
route-dependent, and by assuming local c-constancy,
these "apparent" tirneflow differences would then turn
into "apparent" gravitational gradients between the
Object and the surrounding observers - the objects
motion would appear to have an associated gravitational
field. The moving body would seem to be producing
something like the "tilted gravitational well"
description of section 9.12, we'd not be able to say
that the metric stays flat when confronted with masses
with significant relative velocity, we'd have ragging
and gravitomagnetism as fundamental effects, and we'd
be led naturally towards c equivalence principle and
the "most general" version of the general principle of
relativity.

SO, although SR tends to be considered as an
observerspace theory, it doesn't fully embrace
observerspace principles ... if it had, it would have
ended up as a different class of theory, with a
different lightspeed propagation model and different
equations of motion. Its application of the PoR to
"frames" is necessarily one stage removed from direct
observation.

Your sycophancy will not work, Honest Roberts. Perimeter Institute is
closed for you forever. The "experts" you worship so desperately are
so silly that they don't even know that both Einstein's and Newton's
theories predict light bending in a gravitational field:

http://streamer.perimeterinstitute.ca/mediasite/viewer/NoPopupRedirector.aspx?pe
id=5f32739a-624d-4ec8-9ecc-4d44d3d16fe9&shouldResize=False
Lee Smolin: "Newton's theory predicts that light goes in straight
lines and therefore if the star passes behind the sun, we can't see
it. Einstein's theory predicts that light is bent...."

As you can see, Lee Smolin does not need you Honest Roberts. He is
much sillier than you and if you go to the Perimeter Institute he will
have to leave....

Pentcho Valev
pvalev@yahoo.com

xxein:  You are truly funny at times.  The pot calling the kettle
black and you don't even know which one you are.

Basing the core physical relationships for how matter interacts with
other matter by exchanging EM signals ... by presupposing a universe
in which matter doesn't exist //as a point of principle// ... is a bit
of a stretch. It's a neat trick if you can get away with it, but
there's no guarantee that the results are definitely going to be real
physics.

The "empty universe" argument is a bit like asking, what sound does a
tree make when it falls in the forest ... if there's nobody there to
hear it ... and also no tree ... and also no forest.

And from the perspective of "acoustic metric" physics, the "local
limit" argument is like asking what sound a tree makes when it falls
in a region that's too small to actually contain a tree in the first
place.

Both approaches have the //mathematical// advantage that they allow a
mathematician to quickly generate a single unambiguous set of
equations (those of special relativity).
But if we wanted to be able to say that those equations were
mathematically //proven// to be the equations that describe the
interactions of real matter, we'd need to do a bit more work than
this. We'd need to demonstrate that the form of the equations doesn't
change when we introduce real matter into our "empty universe" model,
or when we allow the possibility that real moving matter might be
associated with local spacetime distortions.

If you try that exercise, you should find that when we "switch off"
the extreme idealisations of SR, the equations seem to change -- the
exercise suggests that the particular form of special relativity might
be specific to a set of conditions that depend on the absence of real
matter in the region being modeled.

Wolfgang Rindler::

Rindler finishes his paper by pointing out that once we'd put together
the basics of a general theory based on spacetime curvature (without
assuming or knowing anything about special relativity), we'd then
naturally be able to get Einstein's special theory as a flat-spacetime
limit of it.
Which is correct.

But if such a theory //had// been proposed in the C19th, it's not
obvious that the C19th mindset would have decided that it was a good
idea to try to develop an offshoot theory that didn't use the new
curved-spacetime geometry.

In real life, the guys that attempted to construct curved-space models
in the C19th were eventually crushed by their collective inability to
get the damned things to work (because they didn't realise that they
needed curvature to be applied in four dimensions rather then three).
Their failure left open the problem of how to reconcile lightspeed
constancy with inertial mechanics, which ended up being addressed
instead as a flat-spacetime problem by Poincare, Lorentz and Einstein.
But if the curved-spacetime solution had arrived //first//, it would
have caught the first wave of "curvature" enthusiasts like William
Kingdon Clifford (1845-1879, the "Clifford algebra" guy):

, who was already arguing that ==all== physics was curvature.

The curved-spacetime model would have suggested velocity-dependent
gravitomagnetic effects between moving gravitational sources,
Clifford's approach would then have suggested that we try to apply the
same rules to particles (considered as "micro-sources") and the
resulting local lightdragging prediction would have chimed nicely with
experimental verifications in the 1850's that moving bodies dragged
light.

The C19th aether theorists could then have gotten onboard and helped
thrash out the geometrical details of a relativistic acoustic metric,
and the model could then have snowballed, sucking in C19th experts
from a range of disciplines. The operating characteristics of acoustic
metrics would probably have been more familiar to aether theorists
than to "modern" physicists, and the new model would have fixed the
arbitrariness of C19th dragged-aether models by giving them a
geometrically-derivable foundation. The new model could also have been
claimed by the surviving emission-theory guys as a success for
//their// subject, since it'd have finally reconciled Newtonian optics
with wave theory.

Finally, when the "Ultraviolet Catastrophe" came along,
http://en.wikipedia.org/wiki/Ultraviolet_catastrophe
and people were forced to consider quantum effects, the QM guys,
desperate for some sort of physical model to attach their statistics
to, would probably have realised that some of the "craziness" of QM
seemed to correspond suspiciously well to the analogous "craziness"
that you get when you try to project the contents of an acoustic
metric onto a simpler surface.

So we'd have had a convergence of the C19th geometers, the C19th
aether theorists, the C19th emission theory guys and the other C19th
Newtonian guys, and we'd have had the pioneers of quantum mechanics
also coming onboard a few years later.

Now, set against that lumbering juggernaut, I'm not sure how any poor
soul subsequently discovering special relativity would have had a
snowball's chance in hell of getting SR accepted as anything other
than an interesting partial group-theory "echo" of what would have
been considered to be the "proper" physics.  

====

Note that although it probably seems inconceivable to a modern
physicist that a general theory could work without SR, in the
alternative scenario it would probably appear at least as
inconceivable that a general theory could work satisfactorily //with//
SR. Since moving to SR-based physics would break the alternative
timeline's default compatibility between GR and QM, that timeline's
physicists might take this as proof positive that SR-based physics
wasn't workable. Since they'd already have c-constancy licked as a
local effect, it wouldn't have been immediately obvious why they
should further complicate their system by introducing SR.

How could we convince that timeline's physicists that they'd totally
misunderstood the basic nature of physics? Perhaps we could suggest
that they study the properties of both versions of physics, work out
where the two sets of physical predictions diverge, and then carry out
some comparative tests that would (hopefully) tell them that we were
right and they were wrong. If they hadn't already tried these tests,
we could point to this as evidence that their science was sloppy, and
their physics probably inferior to ours.

But unfortunately, they'd be able to point out that =we= hadn't
conducted a proper comparative study of the two paths either, and that
=we= hadn't conducted tests designed to distinguish between them.

They'd also have the advantage over us that they'd be able to say that
their versions of QM and GR had worked well together almost from the
beginning, whereas our "SR-based" GR still wasn't compatible with
quantum theory after ninety-something years.

===

Note also that the split between the two alternative histories doesn't
depend on any physical experimental data: It seems to be a sheer
historical accident that we ended up on this theoretical path rather
than the other one. It's a small step from gravitational shifts
(predicted by John Michell way back in the //Eighteenth// Century,
http://en.wikipedia.org/wiki/John_Michell
1784) to gravitational time dilation (and curved spacetime).
If anything, it seems rather odd that GR //didn't// appear until the
C20th, given the brilliant guys who were trying to get spatial
curvature to work in the C19th. If they'd just experimented with
applying curvature in one extra dimension, they might have hit the
jackpot.  

So although we're currently convinced of the inevitable correctness of
the SR-based approach, that degree of conviction doesn't seem to carry
any deeper significance. If history had played out slightly
differently, we might now be just as deeply convinced that the
SR-based approach was obviously wrong, without any of our experiments
having turned out differently.

Human nature's a funny thing.

Actually, most of them do seem to relate to SR (at least, on the list
that I drew up).

Once you've looked at how the properties of a general theory based on
SR compare to those of a general theory //not// based on SR, it's
easier to see which aspects of current theory are consequences of the
SR-based approach, and which aren't.

But in order to see  the dependencies between SR and various aspects
of current GR, you have to actually do that exercise (or know the
results of someone else doing it).

We agree that the current default implementation of a general theory
(Einstein's) explicitly reduces to the physics of special relativity.

Where we seem to disagree is about whether an alternative
implementation of the general principle of relativity -- an
alternative general theory of relativity -- would necessarily have to
reduce to the physics of SR.

Most GR people seem to genuinely believe that the argument of "SR as a
geometrical limit to GR" means that any variation on GR has to reduce
to the //physics// of SR as a geometrical necessity ... but Clifford's
idea of "all physics as curvature" provides a logical counterexample
-- a conceivable system of physics in which a flat-spacetime limit
doesn't represent a physical solution.

One counterexample is sufficient to destroy a mathematical proof, so
the "reduction to SR" argument isn't a general one until we can find
some way of proving that a Cliffordian system of physics can't work.

(And by "proving that it can't work", I mean more than just "proving
that it's not compatible with special relativity". Of course a
curvature-based model isn't compatible with special relativity --
that's what makes the idea important)

In the case of a new or unfamiliar theory, a certain amount of
thinking is often necessary in order to explore what the structure of
that new system ought to be. Sometimes you arrive at a structure by
successive approximation or by the progressive elimination of
alternatives, with the theory's "logical derivation" only being
produced afterwards for public consumption.

To someone who is "taught" a theory, the final polished version of the
theory will tend to appear as an unavoidable result of a set of
definitions and starting assumptions that lead inevitably to it, and
to nothing else.
To someone else whose interest is the construction of theories, they
may look at the same theory and see not an inevitable path from known
principles to a single outcome, but a branching range of alternative
half-possibilities that the theorist has managed to rule out by using
particular wordings or syntax.
Most of those combinations of alternative meanings won't work
together, but sometimes there'll be enough ambiguity in a general
principle to allow you to branch off in a different direction, or
sometimes when you break a theory into its component parts, you'll
find that by adding or removing a part, the rest of the pieces can be
fitted together in a different way.

So yes, for a given specified theory, the structure should (ideally)
be completely defined and non-negotiable.

But for a ==class== of theory there can sometimes be suggestions of
possible alternative implementations. Most of them probably won't
work, or will be considered "bad" in context because they conflict
with some feature that a theory requires, but occasionally you might
find enough leeway in the choices that were originally available to
the author to allow a different choice and a different structure.

I find that people who've spent a lot of time in the educational
system tend to be taught to expect only one solution to a given
problem ("first-answer syndrome"). Once they've been taught the
"standard" answer, "A", they tend to fixate on it and assume that it's
the //only// answer, and if you come up with a more subtle solution,
"B", they'll tend to tell you that you're dumb for not recognising the
obvious correctness of the first answer, "A", which everybody who
knows anything about the subject knows is The Right Answer.

You can try to explain to them that yes, you //do// understand "A",
but you're more interested in this other, more obscure thing, "B" ...
specifically //because// it doesn't correspond to what's in the books
...  and they'll reply, no, no,  the correct answer is "A", so there
can't be another answer "B", by definition ... you clearly haven't
understood answer "A", let me repeat the arguments for "A" once more,
so that you understand them ...

=Erk= (Eric Baird)   http://www.youtube.com/user/ErkDemon

On Jul 13, 3:32 am, stevendaryl3...@yahoo.com (Daryl McCullough)
wrote:

We've explained this to Baird [this is probably Baird] before.
Obviously if he was educable his misconceptions would have been fixed
before he published them in a book for all to ignore.

This is a common misconception. But it's the postulates of special
relativity that are tied to unaccelerated reference frames. The speed of
light is invariant in an unaccelerated reference frame, and the
principle of relativity is applied to unaccelerated reference frames.
But special relativity certainly can handle accelerated reference
frames. The process is basically one of boosting in succession from one
inertial frame to another and taking a limit, and we assume that the
acceleration itself doesn't introduce any novel physics. In other words,
take the derivative with respect to time of the Lorentz transformations
as many times as you like. There are many articles in the literature
about the accelerating rocket, the rotating disk, identically
accelerated twins, and so on.

Accelerated reference frames, like the uniformly accelerating rocket,
introduce many gravity-like features, like a clock in the nose ticking
faster than a clock in the tail. But the gravity of Earth can't be
modeled by a uniformly accelerating rocket because the gravity of Earth
has a different magnitude and different direction at different points in
space. General relativity adds a relation between intrinsic curvature
and the stress-energy tensor, and that has many interesting results.
Except for that, the two theories are not actually radically different--
once you have your metric, and you define an observer frame (which could
be accelerated), you can work out your trajectories. But special
relativity texts give you all the easy problems, so students wind up
using the pseudo-unitary metric for everything and wondering why they
should bother with the complication of a metric at all.

Harry, it sounds to me as if you don't like the direction of the
quote, can't think of any way to counter it, and are therefore
inventing a scenario in which Einstein was supposedly soft in the head
at the time that he wrote the article ... because you can't come up
with a proper counter-argument.  

That's not very nice behaviour.

====

Einstein's April 1950 article for Scientific American was a review
piece on the history and development of relativity theory (and its
foundations), leading up to his (then) current view of the subject.
It was for a special issue of Scientific American, with Einstein on
the cover.

It's been republished in the "Ideas and Opinions" compilation
(pp.341-356), where it takes up about 14-15 pages, and for those with
an aversion to visiting libraries or buying books, it's also available
online, on the Encarta website:

http://encarta.msn.com/sidebar_761599216/einstein_on_gravitation.html

This article was presumably written on a commercial basis for
Scientific American, making SciAm the commissioning body and copyright
holder, so it's not available on //my// website, but Encarta seem to
have gotten permission from SciAm to use the entire article on theirs.
The full paragraph in question (here lifted from Encarta) says:

I think that most people who've read the full piece would agree that
it doesn't come across as something written by a feeble-minded
individual with a faltering recollection of special relativity. Okay,
so a lot of people didn't agree that he was on the right track with
his unified field theory, but if you ask those people how far they've
gotten since with //their// UFT's ... well ...

Einstein continued publishing scientific papers and other articles all
the way up to 1955. These included the fifth appendix to his "popular"
relativity book (1952) and a second appendix to the republished
Princeton Lectures, "The Meaning of Relativity", in about 1950
(revised 1954). He's supposed to have been offered the Presidency of
Israel in 1952, and been smart enough to turn them down.

Dismissing Einstein's 1950 writing on the grounds of age is a bit low,
I think. Certainly some people sink into a rut as they age and lose
the ability to take in new ideas, but the article shows Einstein doing
the opposite, exploring new possibilities even if they seemed to be at
odds with one of the theories that had made him famous.

Einstein wrote in 1927 that the thing that impressed him about Isaac
Newton was Newton's ability to see the problems with his own models
better than his supposed critics could. I think Einstein was probably
striving for the same thing: to be the guy who understood the
potential problems in his own theories better than anyone else.

It's a good discipline to have.

...

=Erk= (Eric Baird)      http://www.worldcat.org/oclc/181743934

Okay, I've turned up Einstein's medical case history
Turns out that Einstein's medical problem was an abdominal aortic
aneurism. His symptoms were attacks of upper abdominal pain lasting
2-3 days every three or four months, caused by inflammation of the
gall-bladder due to pressure from the aneurism.
He was diagnosed in ~1950, and had an operation.

http://www.medscape.com/viewarticle/436253 
   

So, although you describe Einstein being "already on or near his
deathbed" in 1950, this page indicates that after spending three weeks
recovering from his operation (in ~1950?), Einstein seems to have been
"out and about" for the next ~five years until his aneurism finally
burst. There's no mention in this patient history of him visiting a
hospital again during those five years.

Rather than dying in 1955

, Einstein's terminal hospitalisation only seems to have lasted five
_days_.

If you have an information-source that disagrees with this account,
could you let us know what it is?

Cheers,
=Erk= (Eric Baird)
http://search.barnesandnoble.com/booksearch/isbninquiry.asp?ean=0955706807