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Science Forum Index » Mathematics Forum » Gravity Energy and Lenny Susskind's Lanscape
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| Jack Sarfatti |
 Posted: Fri Dec 19, 2003 4:39 pm |
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On Friday, December 19, 2003, at 11:47 AM, Paul Zielinski wrote:
Jack Sarfatti wrote:
On Wednesday, December 17, 2003, at 06:38 PM, Paul Zielinski wrote:
Jack Sarfatti wrote:
Part III
On Monday, December 15, 2003, at 04:27 PM, Paul Zielinski wrote:
PZ: Why make it look superficially as if the physical effects of
acceleration do not mark off inertial frames if
in fact they do?
You cannot throw away differential geometry.
JS: Huh?
Standard GR has a difference between LIFs and LNIF's, it's simply
that the local field equations do not depend on the difference.
It's tensors all the way Jose.
PZ: The point is that general covariance alone is not actual general
relativity -- although it can look superficially like general
relativity in a formally general covariant theory.
....
PZ: Einstein wished to extend the special principle of relativity into
a general theory in which the inertial
frames were not marked off as physically special.
JS: Obviously.
PZ: This is not at all obvious. And it turns out it didn't actually
work, since there
is in fact no Einsteinian strict equivalence.
JS: I do not understand why you keep saying this? I am not sure where
the miscommunication is.
The g-force is locally equivalent to an inertial force. The LOCAL
g-force on a "point" test particle vanishes when
that test particle is a LIF on a time-like geodesic. Ignoring torsion
and non-metricity of course.
In contrast, the "curvature tensor" local relative tidal acceleration on
two geodesic test particles does not vanish in the limit that the
separation shrinks to "zero" (neglecting Lp effect) need not vanish even
though the g-force on each test particle does vanish. That's it.
PZ: Einstein's idea of extending the special principle of relativity,
and what is wrong
with this, is explained very clearly in Roberto Torretti's highly
regarded "Relativity
and Geometry" (Dover 1996):
"While Einstein's description of his strong Principle of Equivalence...
as 'a
natural extrapolation of one of the most universal empirical statements
of physics'
is not unjustified, his original presentation of it as a generalization
of the Relativity
Principle is completely misleading. The physical equivalence of
reference frames
at rest in a homogeneous gravitational field and uniformly accelerated
frames
does not obliterate the physical inequivalence between the latter and
inertial
frames... It simply entails that a reference frame at rest in a
gravitational field
cannot be inertial."
JS: What does "obliterate" mean? Of course Einstein knew there is a
physical difference between LIF's and LNIF's
mutually coincident at same "point" event P. LIF observers are
weightless, LNIF observers feel weight from non-gravity
electrical reaction forces putting them off a geodesic world line
through P. The point is that there is a local tetrad map eu^a(P) and
inverse from
LIF to LNIF in which the local geometrodynamic field equation has "same"
form i,e,
tuv("Marble" Geometry) + Tuv("Wood" Matter) = 0 in LNIF at P
tab ("Marble" Geometry) + Tab("Wood" Matter) = 0 in LNIF at SAME P
t..(Geometry) = (String Tension)G..(Einstein)
G..(Einstein) = R..(Ricci) - (1/2)R(Ricci)g..
gab = Minkowski LIF metric at P
guv = LNIF metric at same P
t..(Geometry) = 0 in ALL FRAMES
in non-exotic vacuum where /\zpf = 0
corresponding to a large critical VACUUM COHERENCE BTW
http://qedcorp.com/APS/EmergentGravity.pdf
Yes, a local frame "at rest" in a gravity field is LNIF. Whenever there
is a g-force you are in a LNIF.
The interesting idea here is that you use TWO test particles, each
feeling ZERO g-force, to measure
their intrinsic curvature relative tidal acceleration if one is there.
PZ: "Far from generalizing the Principle of Relativity, [the equivalence
principle]
drastically alters its meaning and restricts its scope."
("Relativity and Geometry", Section 5.2 pp 135-136 )
JS: Much Ado About Nothing IMHO.
PZ: And here is Ohanian and Ruffini:
"Unfortunately, Einstein's statement [Einstein (1916)] has often been
generalized
to sweeping assertions about all laws of physics about all laws of
physics being
the same in a laboratory freely falling in a gravitational field and in
another
laboratory far away from any field... "
JS: O & R do not say Einstein did that. BTW Hal Puthoff does do that in
his PV "Tables" on K.
OR: "Such generalizations are unwarranted since...
even quite simple devices will signal the presence of a true
gravitational field by
their sensitivity to tidal forces and will therefore permit us to
discriminate between
a gravitational field and the pseudo-force of acceleration."
JS: Exactly what I have said all along. This is purely a semantic issue
on how to use informal language precisely and clearly.
There is no new physics here. Einstein understood all this.
"This statement [of the Einstein equivalence principle] is true only in
a limited sense.
Gravitation and acceleration are equivalent only as far as the
translational motion
of point particles is concerned... If the rotational degrees of freedom
of the motion
of the masses are taken into consideration, then the equivalence fails."
JS: Of course, I have repeatedly said the same thing.
"Gravitation and Spacetime", Second Edition (Norton (1995), Section 1.9)
PZ: So there is at this point no physical reason to take Einstein's
belief in the "complete
physical equivalence" of gravitational and inertial fields seriously,
except in the sense
of a *limited heuristic analogy*.
JS: Depends what one means by vague "complete". This is not a big deal.
"Everyone" understands
what OR say and agrees with it. It's all in MTW.
PZ: Which is what I have been arguing for at least a year.
JS: No one ever disagreed with that. You have been very obscure about
this getting it mixed up with the Yilmaz
issue. Every important idea in physics is a "limited heuristic analogy"
IMHO. There are no absolute truths in science.
PZ: If so, then there is no reason to expect inertial forces to
contribute to or alter the physical
stress-energy of the gravitational field, and thus no deep reason to
demand that this
physical stress-energy density be annihilated *anywhere* in an LIF --
contrary to the bold
Einsteinian assertions of Charles Misner et al.
JS: This does not follow logically from what was said before.
Indeed, I show that when quantum zero point energy is included in the
exotic w = -1 vacua of both "dark energy"
and "dark matter" as LOCAL fields, which in FRW case limit to Einstein's
"Cosmological Constant" that
tuv(Marble Geometry Vacuum) = - tuv(Exotic Vacuum)
tuv(Exotic Vacuum) = (String Tension)/\zpfguv
/\zpf = 0 in non-exotic vacuum
/\zpf > 0 repulsive dark energy exotic vacuum
/\zpf < 0 attractive dark matter exotic vacuum
/\zpf = Lp^-2[Lp^3|Vacuum Coherence|^2 - 1]
guv = (Minkowski)uv + du,v + dv,u
du = Lp^2(arg Vacuum Coherence),u
,u = ordinary partial derivative
Lp^2 = hG/c^2 = 1 Bekenstein "BIT" on surface of Susskind's
"World Hologram" that has the 3D projection image that is ordinary
uncompactified space.
When Vacuum Coherence = 0 we have globally flat Minkowski space-time,
but with a huge cosmological constant. This is unstable and is why we have
inflation IMHO.
* /\zpf = 0 is like Lenny Susskind's supersymmetry limit where the vacua
on the
"Landscape" of "Megalopolis" (Francis Ford Coppola's new movie) do not
depend on the "moduli" of the extra hyperspace dimensions of Calabi-Yau. |
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