A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Astronomy and Astrophysics » Astronomy Misc
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Topics in Quantum Gravity 1



 
 
Thread Tools Display Modes
  #1  
Old July 17th 07, 01:57 AM posted to sci.physics,sci.math,sci.astro,sci.physics.relativity,sci.physics.particle
Jack Sarfatti
external usenet poster
 
Posts: 113
Default Topics in Quantum Gravity 1



What's wrong is that Hal has not identified all of the relevant
parameters of the problem of the structure of the electron. There is no
gravity in his model. In fact gravity gets stronger as the scale
decreases. This last statement comes from a Wignerian analysis of
quantum gravity measurement as shown by Ng & Van Dam below.

Let me make it as simple as possible, but not, like Hal's model, simpler
than is possible.

You have a shell of electric charge. How do you prevent it from
exploding under its self-repulsion?

You have two options:

1. Press in radially on the thin shell of charge from outside the shell.

2. Suck in from the inside of the shell.

Hal chooses 1. The correct answer is 2.

The problem with 1 is that it requires too much zero point energy ZPE
density on the outside of the shell. So much that the universe could not
exist. Hal needs ~(hc/Lp^2)(mc/h)^2 ZPE energy density outside the shell
of charge to contain the charge. The virtual photon density outside the
charge has w = -1 and is positive. Therefore, the pressure is negative.
Hal cannot use w = +1/3 DeWitt outside the charged shell. DeWitt's
solution is inside the charged shell.

Pressure acts in two different ways, mechanically and gravitationally.
Usually the gravitation of pressure is much weaker than its mechanical
action. Note that this mechanical action is basically electrical in
origin. The Casimir effect is mechanical.

Hal models his electric shell as empty inside with mechanical pressure
from virtual photons on the outside pushing radially inward on the
charge. This is his picture. It's wrong for several reasons.

1) the virtual photon pressure on the outside is negative not positive
because w = -1 on the outside.

2) there are virtual photons on the inside and from Dw Witt w = +1/3 on
the inside.

Therefore, mechanically the positive pressure on the inside pushes the
charge outward, and the negative pressure on the outside also sucks the
charge radially outward. Therefore, there is no mechanical (electrical)
containment of the shell of charge at all!

Remember pressure is the component of force along the normal unit vector
of a surface per unit area of that surface.

That's the mechanical action. The gravity action of pressure is opposite
to the mechanical action, although usually it is too small to notice
compared to the mechanical action in every case except for this one of
zero point energy!

Positive pressure gravitates attractively. Therefore, a positive
pressure inside the shell of charge will suck the charge radially
inward. The issue is how strong is it? Also negative pressure outside
the shell of charge anti-gravitates pushing the charge radially inward.

Now it turns out that the zero point energy density inside the shell of
charge is

(hc/Lp^2)(mc/h)^2 ~ 10^-27 10^10 10^66 10^-22 ergs/cc ~ 10^(76-49)
ergs/cc ~ 10^27 ergs/cc

The induced gravity effect of this ZPE from Einstein's GR is
approximately from

Guv + /\zpfguv = 0

limits to radial Poisson equation

d^2U/dr^2 ~ c^2/\zpf ~ c^2(mc/h)^2

U = ZPE induced gravity potential energy per unit test mass.

Note if /\zpf ~ constant

U ~ (1/2)c^2(mc/h)^2r^2

3D harmonic oscillator.

In fact, the ZPE density outside the charge, if there are no further
boundaries is very small

~ (hc/Lp^2)(1/Hubble Radius)^2

PS the above formula and also

(hc/Lp^2)(mc/h)^2

are both consistent with the world hologram hypothesis - see below.

On Jul 15, 2007, at 3:30 PM, Jack Sarfatti wrote:

PS There is no mention of ZPE induced gravity in Hal's paper. Therefore
the paper is wrong. Hal has not asked the correct question to solve the
problem - neither did Casimir of course.

On Jul 15, 2007, at 1:30 PM, wrote:


Hi Paul, attached is my latest use of the ZPE formalism, just came out
in Int. Jour. Theor. Phys. Shows how the formalism leads naturally to a
point electron without infinite mass generated by the coulomb fields.

Cheers,
Hal


http://arxiv.org/abs/gr-qc/0403057 v1 13 Mar 2004

“In essence, the holographic principle says that although the world
around us appears to have three spatial dimensions, its contents can
actually be encoded on a two-dimensional surface, like a hologram …
According to the holographic principle, the number of degrees of freedom
that this cubic region can contain is bounded by the surface area of the
region in Planck units, i.e., l^2/LP^2instead of by the volume l^3/LP^3
of the region as one may naively expect. This principle is counter-
intuitive, but is supported by black hole physics in conjunction with
the laws of thermodynamics, and it is embraced by both string theory and
loop quantum gravity … the “strange” holographic principle has its
origin in quantum fluctuations of spacetime.”

I. And also by my theory where the emergent coherent macro-quantum
vacuum condensate tetrad 1-forms are

e^a = I^a + (LP^2/l^2)^1/3A^a

A^a= M^a^a

is the renormalizable spin 1 Yang-Mills tetrad field "square root" of
Einstein's non-renormalizable spin 2 tensor theory. The Mystery Matrix
of Goldstone phase 0-forms of the coherent post-inflationary vacuum is

M^a^a= Theta^a/\dPhi^a- dTheta^a/\Phi^a

Where Einstein's 1916 GR is recovered in the bilinear forms of the spin
1 tetrad fields

ds^2 = guvdx^udx^v = e^aea

That in a nutshell is my new and completely original theory in my

http://arxiv.org/abs/gr-qc/0602022

Emergent Gravity and Torsion: String Theory Without String Theory, Why
the Cosmic Dark Energy Is So Small

Jack Sarfatti
(Submitted on 7 Feb 2006 (v1), last revised 11 Jul 2007 (this version, v21))
A surprisingly simple holographic explanation for the low dark energy
density is suggested. I derive the Einstein-Cartan disclination
curvature tetrads and the physically independent dislocation torsion gap
spin connections from an "M-Matrix" of non-closed Cartan 1-forms made
from 8 Goldstone phase 0-forms of the vacuum ODLRO condensate inflation
field in which the non-compact 10-parameter Poincare symmetry group is
locally gauged for all invariant matter field actions. Quantum gravity
zero point vacuum fluctuations should be renormalizable at the spin 1
tetrad level where there is a natural scale-dependent holographic
dimensionless coupling (hG/\zpf/c^3)^1/3 ~ (Bekenstein BITS)^-1/3. The
spacetime tetrad rotation coefficients play the same role as do the Lie
algebra structure constants in internal symmetry spin 1 Yang-Mills local
gauge theories. This suggests an intuitively pleasing natural
"organizing idea" now missing in superstring theory. It is then clear
why supersymmetry must break in order for our pocket universe to come
into being with a small w = -1 negative pressure zero point exotic
vacuum dark energy density. Just as the Michelson-Morley experiment gave
a null result, this model predicts that the Large Hadron Collider will
never find any viable on-mass-shell dark matter exotic particles able to
explain Omega(DM) ~ 0.23 as a matter of fundamental principle, neither
will any other conceivable dark matter detector because dark matter
forming galactic halos et-al is entirely virtual exotic vacuum w = - 1
with positive irreducibly random quantum zero point pressure that mimics
w = 0 CDM in its gravity lensing and all effects that we can observe
from afar.

Comments: This version is the second major revision addressing several
unresolved fundamental empirical problems
Subjects: General Relativity and Quantum Cosmology (gr-qc)
Cite as: arXiv:gr-qc/0602022v21

II. Next to Ng & Van Dam

"SPACETIME FOAM, HOLOGRAPHIC PRINCIPLE, AND BLACKHOLE QUANTUM COMPUTERS

Y. JACK NG AND H. VAN DAM

Institute of Field Physics, Department of Physics and Astronomy,
University of North Carolina, Chapel Hill, NC27599-3255,USA E-mail:


Spacetime foam, also known as quantum foam, has its origin in quantum
fluctuations of spacetime. Arguably it is the source of the holographic
principle, which severely limits how densely information can be packed
in space. Its physics is also intimately linked to that of black holes
and computation. In particular, the same underlying physics is shown to
govern the computational power of black hole quantum computers.

1. Introduction

Early last century, Einstein’s general relativity promoted spacetime
from a passive and static arena to an active and dynamical entity.
Nowadays many physicists also believe that spacetime, like all matter
and energy, undergoes quantum fluctuations. These quantum fluctuations
make spacetime foamy on small spacetime scales. (For a discussion of the
relevant phenomenology and for a more complete list of references, see
Ref. 1.)

But how large are the fluctuations? How foamy is spacetime? Is there any
theoretical evidence of quantum foam? In what follows, we address these
questions. By analysing a gedanken experiment for spacetime measurement,
we show, in section 2, thatspacetime fluctuations scale as the cube root
of distances or time durations.Then we argue thatthis cube root
dependence is consistent with the holographic principle. In section 3,
we discuss how quantum foam affects the physics of clocks (accuracy and
lifetime) and computers (computational rate and memory space). We also
show that the physics of spacetime foam is intimately connected to that
of black holes, giving a poor man’s derivation of the Hawking black hole
lifetime and the area law of black hole entropy. Lastly a black hole
computer is shown to compute at a rate linearly proportionalto its mass.

2. Quantum Fluctuations of Spacetime

If spacetime indeed undergoes quantum fluctuations, the fluctuations will
show up when we measure a distance (or a time duration), in the form of
uncertainties in the measurement. Conversely, if in any distance (or
time duration) measurement, we cannot measure the distance (or time
duration) precisely, we interpret this intrinsic limitation to spacetime
measurements as resulting from fluctuations of spacetime.

The question is: does spacetime undergo quantum fluctuations? And if so,
how large are the fluctuations? To quantify the problem, let us consider
measuring a distancel. The question now is: how accurately can we
measure this distance?Let us denote by dl the accuracy with which we can
measurel. We will also refer to dl as the uncertainty or fluctuation of
the distancelfor reasons that will become obvious shortly. We will show
that dl has a lower bound and will use two ways to calculate it.Neither
method is rigorous, but the fact that the two very different methods
yield the same result bodes well for the robustness of the conclusion.
(Furthermore, the result is also consistent with well-known
semi-classical black hole physics. See section 3.)

3. Gedanken Experiment. In the first method, we conduct a thought
experiment to measure l.The importance of carrying out spacetime
measurements to find the quantum fluctuations in the fabric of spacetime
cannot be over-emphasized. According to general relativity, coordinates
do not have any intrinsic meaning independent of observations; a
coordinate system is defined only by explicitly carrying out spacetime
distance measurements.Let us measure the distance between two points.
Following Wigner 2, we put a clock at one point and a mirror at the
other. Then the distance l that we want to measure is given by the
distance between the clock and the mirror. By sending a light signal
from the clock to the mirror in a timing experiment, we can determine
the distance l. However, quantum uncertainties in the positions of the
clock and the mirror introduce an inaccuracy dl in the distance
measurement. We expect the clock and the mirror to contribute comparable
uncertainties to the measurement. Let us concentrate on the clock and
denote its mass by m. Wigner argued that if it has a linear spread dl
when the light signal leaves the clock, then its position spread grows
to dl+hl(mcdl)^-1 when the light signal returns to the clock, with the
minimum at dl =(hl/mc)^1/2."

[Note by JS: this is the geometric mean of the shortest Compton quantum
length and the “longest” length we are measuring. No gravity as yet.]

"Hence one concludes that

dl^2 hl/mc (1)

General relativity provides a complementary bound.To see this, let the
clock be a light-clock consisting of a spherical cavity of diameter D,
surrounded by a mirror wall of mass m, between which bounces a beam of
light. For the uncertainty in distance measurement not to be greater
than D, the clock must tick off time fast enough that
D/c dl/c. But D, the size of the clock, must be larger than the
Schwarzschild radius rS = 2Gm/c^2 of the mirror, for otherwise one
cannot read the time registered on the clock. From these two
requirements, it follows that

dl Gm/c2 (2)

The product of Eq. (2) with Eq. (1) yields Eq. (3)

dl [(hl/mc)(Gm/c2)] 1/3 = (LP2l)1/3 (3)

where LP = (hG/c3)^1/2 is the Planck length. (Note that the result is
independent of the mass m of the clock and, hence, one would hope, of
the properties of the specific clock used in the measurement.) The end
result is as simple as it is strange and appears to be universal: the
uncertainty dl in the measurement of the distance l cannot be smaller
than the cube root of LP^2l.

Obviously the accuracy of the distance measurement is intrinsically
limited by this amount of uncertainty or quantum fluctuation. We conclude
that there is a limit to the accuracy with which one can measure a
distance; in other words, we can never know the distance l to a better
accuracy than the cube root of LP^2l .

Similarly one can show that we can never know a time duration tto a
better accuracy than the cube root of LP^2t/c2 = tP^2t where tP= LP/c is
the Planck time. Because the Planck length is so inconceivably short,
the uncertainty or intrinsic limitation to the accuracy in the
measurement of any distance, though much larger than the Planck length,
is still very small. For example, in the measurement of a distance of
one kilometer, the uncertainty in the distance is to an atom as an atom
is to a human being.

4. The Holographic Principle. Alternatively we can estimatedlby applying
the holographic principle. 4,5 In essence, the holographic principle 6
says that although the world around us appears to have three spatial
dimensions, its contents can actually be encoded on a two-dimensional
surface, like a hologram. To be more precise, let us consider a spatial
region measuring l by l by l.According to the holographic principle, the
number of degrees of freedom that this cubic region can contain is
bounded by the surface area of the region in Planck units, i.e.,l^2/LP^2
instead of by the volume l^3/LP^3 of the region as one may naively
expect. This principle is counterintuitive, but is supported by black
hole physics in conjunction with the laws of thermodynamics, and it is
embraced by both string theory and loop quantum gravity. So strange as
it may be, let us now apply the holographic principle to deduce the
accuracy with which one can measure a distance.

First, imagine partitioning the big cube into small cubes. The small
cubes so constructed should be as small as physical laws allow so that
we can associate one degree of freedom with each small cube. In other
words, the number of degrees of freedom that the region can hold is
given by the number of small cubes that can be put inside that region.
But how small can such cubes be? A moment’s thought tells us that each
side of a small cube cannot be smaller than the accuracy dl with which
we can measure each side l of the big cube. This can be easily shown by
applying the method of contradiction: assume that we can construct small
cubes each of which has sides less thandl. Then by lining up a row of
such small cubes along a side of the big cube from end to end, and by
counting the number of such small cubes, we would be able to measure
that side (of length l) of the big cube to a better accuracy than dl.
But, by definition, dl is the best accuracy with which we can measure l.
The ensuing contradiction is evaded by the realization that each of the
smallest cubes (that can be put inside the big cube) measures dl by dl
by dl. Thus, the number of degrees of freedom in the region (measuring l
by l by l) is given by l^3/dl^3, which, according to the holographic
principle, is no more than l^2/LP^2. It follows that

l^3/dl^3 l^2/LP^2"

JS: Note the algebra

l^3 l^2dl^3/LP^2

l dl^3/LP^2

lLP^2 dl^3

"dl is bounded (from below) by the cube root of lLP^2 the same result as
found above in the gedanken experiment argument. Thus, to the extent
that the holographic principle is correct, spacetime indeed fluctuates,
forming foams of size dl on the scale of l. Actually, considering the
fundamental nature of spacetime and the ubiquity of quantum fluctuations,
we should reverse the argument and then we will come to the conclusion
that the 'strange' holographic principle has its origin in quantum
fluctuations of spacetime."

Rest of paper is deleted from this excerpt as it is peripheral to my
purpose at the moment. BTW I knew Saleckar at UCSD La Jolla in the 60’s.

"One of us (YJN) thanks the organizers of the Coral Gables Conference
for inviting him to present the materials contained in this paper. We
dedicate this article to our colleague Paul Frampton on the occasion of
his sixtieth birthday. This work was supported in part bythe US
Department of Energy and the Bahnson Fund of the University of North
Carolina. We thank L. L. Ng and T. Takahashi for their help in the
preparation of this manuscript.

References

1. Y. J. Ng, Mod.Phys.Lett.A18, 1073 (2003). See also Y.J. Ng,
gr-qc/0401015.

2. E.P. Wigner, Rev.Mod.Phys.29, 255 (1957); H. Salecker and E.P.
Wigner, Phys.Rev.109, 571 (1958).

3. Y.J. Ngand H. van Dam, Mod.Phys.Lett.A9, 335 (1994);A10, 2801 (1995);
in Proc.of Fundamental Problems in Quantum Theory, eds. D.M. Greenberger
and A. Zeilinger, Ann. New York Acad. Sci.755, 579 (1995). Also see F.
Karolyhazy, Nuovo CimentoA42, 390 (1966);T.
Padmanabhan,Class.Quan.Grav.4, L107 (1987); D.V. Ahluwalia,
Phys.Lett.B339, 301 (1994); and N. Sasakura,Prog.Theor.Phys.102, 169 (1999).

4. Y. J. Ng and H. van Dam, Found.Phys.30, 795 (2000);Phys.Lett. B477,
429 (2000).

5. Y. J. Ng, Int.J.Mod.Phys.D11, 1585 (2002).

6. G. ’t Hooft, in Salamfestschrift, edited by A. Ali et al. (World
Scientific, Singapore, 1993), p. 284; L. Susskind, J.Math.Phys.(N.Y.)36,
6377 (1995). Also see J.A. Wheeler, Int.J.Theor.Phys.21, 557 (1982);
J.D. Bekenstein, Phys.Rev.D7, 2333 (1973); S. Hawking,
Comm.Math.Phys.43, 199 (1975).

7. Y. J. Ng, Phys.Rev.Lett.86, 2946 (2001), and (erratum)88, 139902-1
(2002);

Y. J.Ng in Proc.of OCPA2000, eds. N. P. Chang et al. (World Scientific,
Singapore, 2002), p.235.

J.D. Barrow, Phys.Rev.D54, 6563 (1996).

N. Margolus and L. B. Levitin,Physica D120, 188 (1998).

S. Lloyd, Nature(London)406, 1047 (2000)."
---------------------------------------------------
On Jul 15, 2007, at 3:14 PM, Jack Sarfatti wrote:

?
http://www.innovations-report.de/htm...cht-52458.html

The close-packed little (figuratively speaking of course) "green balls"
of "Volume-without-volume" are of size

&l ~ N^1/6 Lp

There is a point gravity monopole inside each "green ball" where the
vacuum ODLRO order parameter drops to zero leaving the two effective 3D
+ 1 Goldstone phases undefined corresponding to this S^2 "vacuum
manifold" of minima for coherently ordered holgraphic ground states of
virtual quanta.

the surrounding surface area is A

N ~ A/Lp^2

In the case of a single electron

A ~ 10^-22 cm^2 corresponding to the shell of electric charge

N ~ 10^-2210^66 ~ 10^44

&l ~ 10^7Lp ~ 10^-27 cm

This is very much like Ken Wilson's "renormalization group" in lattice
gauge theory.

http://nobelprize.org/nobel_prizes/p...on-lecture.pdf

Note also on meaning of holography

"Euclidean quantum field theory in d-dimensional spacetime ~ classical
statistical mechanics in d-dimensional space." A. Zee p. 262 "Quantum
Field Theory in a Nutshell"

Therefore Euclidean quantum field theory on the ANYONIC fractional QM
statistics 3-dimensional spacetime of the surrounding surface ~
classical statistical mechanics in 3-dimensional space, i.e. volume
without volume.


On Jul 15, 2007, at 2:30 PM, Jack Sarfatti wrote:

For the record I think Hal's paper is wrong. He has it inside out.
Indeed the de Witt calculation show that the interior ZPF has w = +1/3
therefore positive ZPF pressure with positive ZPE density /\zpe ~
(mc/h)^2 ~ 10+22 cm^-2 is INSIDE and induces strong enough
micro-gravity to glue the surface electric charge together. The outside
ZPE density has w = -1 and is very small. Hal's picture is qualitatively
wrong IMHO.

Note in the world hologram picture of t'Hooft as further clarified by
Jack Ng's very readable papers (Univ. Maryland):

ZPE density is hc/NLp^4 = (hc/Lp^2)/\zpf

/\zpf ~ 1/NLp^2 ~ (10^66/N)cm^-2

N ~ 10^-2210^66 ~ 10^44

/\zpf ~ 10^22 cm^-2

Very very pretty picture!

It works. It really works semi-quantitatively.

Also the electron is not a point. It is a spatially extended Bohm hidden
variable, but its gravity is so strong that it looks like a point by the
time the scattering momentum transfers are ~ 2mc ~ 1 Mev

Hal's picture only works if you assume that uniform ZPE does not
gravitate. This is wrong and squarely contradicts Einstein's GR as does
his PV model.

Hal's paper shows what not to do.

On Jul 15, 2007, at 1:30 PM, wrote:


Hi Paul, attached is my latest use of the ZPE formalism, just came out
in Int. Jour. Theor. Phys. Shows how the formalism leads naturally to a
point electron without infinite mass generated by the coulomb fields.

Cheers,
Hal


 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Gauge Theory and Quantum Gravity 2 Jack Sarfatti Astronomy Misc 0 May 23rd 07 03:49 AM
Gauge Theory and Quantum Gravity Jack Sarfatti Astronomy Misc 2 May 22nd 07 07:56 AM
Quantum Gravity Topics 1 Jack Sarfatti Astronomy Misc 0 February 20th 07 04:43 AM
Quantum Gravity? [email protected] Astronomy Misc 4 June 11th 05 08:42 PM
QUANTUM AND GRAVITY MECHANICS UNIFIED GRAVITYMECHANIC2 Astronomy Misc 0 October 31st 03 01:54 AM


All times are GMT +1. The time now is 07:04 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.