Go to earthquake WARNING research homepage.
Return to the RS EG Refs. Page
Return to the Previous RS EG Refs. Page
QUANTUM PHYSICS, ABSTRACT QUANT-PH/9502024
From: MANKO@napoli.infn.it
Date: Mon, 27 Feb 1995 16:32:21 +0200 (CET)
Deformation of Partical Distribution Functions due to Q-nonlinearity and Nonstationary Casimir Effect,
Author: V. I. Man'ko
The geometrical phase is shown to be integral of motion. Deformation of
particle distribution function corresponding to nonstationary Casimir effect
is expressed in terms of multivariable Hermite polynomials. Correction to
Planck distribution due to q--nonlinearity is discussed.
QUANTUM PHYSICS, ABSTRACT QUANT-PH/9503001
From: onofrio%38619.hepnet@Csa4.LBL.Gov
Date: Wed, 1 Mar 95 08:23:43 PST
Detecting Casimir Forces through a Tunneling Electromechanical Transducer
Authors: Roberto Onofrio , Giovanni Carugno
We propose the use of a tunneling electromechanical transducer to dinamically
detect Casimir forces between two conducting surfaces. The maximum distance
for which Casimir forces should be detectable with our method is around $1
\mu$m, while the lower limit is given by the ability to approach the surfaces.
This technique should permit to study gravitational forces on the same range
of distances, as well as the vacuum friction provided that very low
dissipation mechanical resonators are used.
CONDENSED MATTER THEORY, ABSTRACT COND-MAT/9505023
From: moraes@guinness.ias.edu (Fernando Moraes)
Date: Fri, 5 May 95 09:35:57 EDT
Casimir effect around disclinations
Author: Fernando Moraes (Institute for Advanced Study, Princeton)
This communication concerns the structure of the electromagnetic quantum
vacuum in a disclinated insulator. It is shown that a nonzero vacuum energy
density appears when the rotational symmetry of a continuous insulating
elastic medium is broken by a disclination. An explicit expression is given
for this Casimir energy density in terms of the parameter describing the
disclination.
CONDENSED MATTER THEORY, ABSTRACT COND-MAT/9505108
From: moraes@guinness.ias.edu (Fernando Moraes)
Date: Tue, 23 May 95 17:12:35 EDT
Enhancement of the magnetic moment of the electron due to a topological defect
Author: Fernando Moraes (Institute for Advanced Study, Princeton)
In the framework of the theory of defects/three-dimensional gravitation, it is
obtained a positive correction to the magnetic moment of the electron bound to
a disclination in a dielectric solid.
QUANTUM PHYSICS, ABSTRACT QUANT-PH/9506005
From: JAEKEL Marc jaekel@physique.ens.fr
Date: Wed, 7 Jun 1995 16:30:40 +0200
Mechanical Effects of Radiation Pressure Quantum Fluctuations Authors: Marc-
Thierry Jaekel (Laboratoire de Physique Th\'eorique de l'Ecole Normale
Sup\'erieure) , Serge Reynaud (Laboratoire Kastler-Brossel)
As revealed by space-time probing, mechanics and field theory come out as
complementary descriptions for motions in space-time. In particular, quantum
fields exert a radiation pressure on scatterers which results in mechanical
effects that persist in vacuum. They include mean forces due to quantum field
fluctuations, like Casimir forces, but also fluctuations of these forces and
additional forces linked to motion. As in classical electron theory, a moving
scatterer is submitted to a radiation reaction force which modifies its
motional response to an applied force. We briefly survey the mechanical
effects of quantum field fluctuations and discuss the consequences for
stability of motion in vacuum and for position fluctuations.
QUANTUM PHYSICS, ABSTRACT QUANT-PH/9506006
From: JAEKEL Marc jaekel@physique.ens.fr
Date: Wed, 7 Jun 1995 16:58:17 +0200
Quantum Fluctuations and Inertia
Authors: Marc-Thierry Jaekel (Laboratoire de Physique Th\'eorique de l'Ecole
Normale Sup\'erieure) , Serge Reynaud (Laboratoire Kastler-Brossel)
Vacuum field fluctuations exert a radiation pressure which induces mechanical
effects on scatterers. The question naturally arises whether the energy of
vacuum fluctuations gives rise to inertia and gravitation in agreement with
the general principles of mechanics. As a new approach to this question, we
discuss the mechanical effects of quantum field fluctuations on two mirrors
building a Fabry-Perot cavity. We first put into evidence that the energy
related to Casimir forces is an energy stored on field fluctuations as a
result of scattering time delays. We then discuss the forces felt by the
mirrors when they move within vacuum field fluctuations, and show that energy
stored on vacuum fluctuations contributes to inertia in conformity with the
law of inertia of energy. As a further consequence, inertial masses exhibit
quantum fluctuations with characteristic spectra in vacuum.
QUANTUM PHYSICS, ABSTRACT QUANT-PH/9506023
From: claudia@cromwell.physics.uiuc.edu (Claudia C Eberlein)
Date: Thu, 15 Jun 95 11:13:57 -0500
Sonoluminescence as quantum vacuum radiation Author: Claudia Eberlein (Dept of
Physics, UIUC, Urbana, IL)
Sonoluminescence is explained in terms of quantum radiation by moving
interfaces between media of different polarizability. It can be considered as
a dynamic Casimir effect, in the sense that it is a consequence of the
imbalance of the zero-point fluctuations of the electromagnetic field during
the non-inertial motion of a boundary. The transition amplitude from the
vacuum into a two-photon state is calculated in a Hamiltonian formalism and
turns out to be governed by the transition matrix-element of the radiation
pressure. Expressions for the spectral density and the total radiated energy
are given.
HIGH ENERGY PHYSICS - THEORY, ABSTRACT HEP-TH/9508086
From: eli@ecm.ub.es (Emili Elizalde)
Date: Fri, 18 Aug 1995 10:14:50 +0200
A precise definition of the Casimir energy, Authors: K. Kirsten , E. Elizalde
The somehow arbitrary definition of the Casimir energy corresponding to a
quantum system in a $d$-dimensional ultrastatic spacetime ---profusely used in
the last years--- which has been critized sometimes for adopting without a
sound argument the minimal subtraction scheme, is shown to be completely
equivalent to the definition steming naturally from the concept of functional
determinant through the zeta-function prescription. This is done by
considering the theory at finite temperature and by defining then the Casimir
energy as its energy in the limit $T\to 0$. The ambiguity in the coefficient
$C_{d/2}$ is understood to be a result of the necessary renormalization of the
free energy of the system. As an example, the Casimir energy corresponding to
a general $(1+2)$-dimensional toroidal spacetime with flat spatial geometry,
parametrized by the corresponding Teichm\"uller parameters, and its precise
dependence on these parameters is obtained under the form of an analytic
function.
------------------------------------------------------------------------
Ernest G. Cullwick. In his book "Electromagnetism and Relativity", published
in 1957, was one of the first to provide an analysis of the probable coupling
between EM and inertial fields. Cullwick realized that Maxwell's equations and
most existing theories of electrodynamics assume that the mass of an electron
is zero. At Maxwell's time this was a reasonable assumption. But it is well
known today that electrons have mass, and therefore an inertial momemtum is
always associated with an electric current. Cullwick suggested in his analysis
that coupling terms between EM and inertia may be very small, but would likely
appear sometime in the future as we go to higher current densities. And he was
one of the first scientists to predict some of the odd effects which can now
seen with superconductors. Cullwick was also one of the first to identify and
attempt an analysis of the relativistic paradoxes and unusual effects which
occur in a rotating EM field. His work still stands today as one of the only
existing efforts to consider the problem of a rotating EM field.
AUTHOR: Cullwick, E. G. (Ernest Geoffrey), 1903-
TITLE: Electromagnetism and relativity : with particular reference
to moving media and electromagnetic induction / by E. G. Cullwick.
EDITION 2d ed.
PUBL.: New York : J. Wiley,
DATE: 1959 (2nd Edition)
SUBJECT: Electromagnetic theory, Relativity (Physics)
AUTHOR: Cullwick, E. G. (Ernest Geoffrey), 1903-
TITLE: The fundamentals of electro-magnetism by E.G. Cullwick.
EDITION 3rd ed.
PUBL.: London, Cambridge U.P.,
DATE: 1966 (3rd Edition)
SUBJECT: Electromagnetism
AUTHOR: Cullwick, E. G. (Ernest Geoffrey), 1903-
TITLE: The fundamentals of electro-magnetism; a restatement for
engineering students and others of physical and theoretical principles in
accordance with modern scientific thought, by E. Geoffrey Cullwick ... With an
appendix and numerous examples on the recently adopted M.K.S. system of
practical units ...
PUBL.: New York, The Macmillan company; Cambridge, Eng., The University press,
DATE: 1939
SUBJECT: Electromagnetism
---------------------------------------------------------------------------
If you work out the metric for EM waves circulating in a cavity you get some
strange results. There is a preliminary discussion of this effect in the
article by Houshang Ardavan, 'Gravitational Waves from Electromagnetic Waves'
in the book "Classical General Relativity," edited by W.B. Bonner, I.N. Islam
and M.A.H. MacCollum (Cambridge Univ. Press, 1984).
It is something I have seen done. At the point in an annular cavity where the
phase velocity goes from less than c to greater than c, a term shows up in the
derived metric of the system that looks like a source term. On the other hand
you have assumed that the metric is source free in the EM region of the
cavity. So you get a solution which contradicts the hypothesis that went into
building the solution. You get something which is possibly unphysical. Now
Einstein's equation and the associated geometry is pretty tricky and it is
easy to get unphysical solutions. The final arbitors of whether a solution is
satisfactory or not is physical reasonability and self consistancy (these are
almost the same thing). The cavity problem seems very physically reasonable
initially, but ends with a self-consistancy problem which appears to be
unphysical. Also, Cauchy's theorem does not apply to this case since it
becomes a mixed type problem (elliptic and hyperbolic PDEs), so the Hawking
singularity theorems don't a priori apply. It is something very interesting,
but to publish it with out being scoffed at would take a lot of work and
possibly inventing some new math.
-- Jim McClune, University of Missouri
-------------------------------------------------------------------------
ROTATING FIELDS IN GENERAL RELATIVITY, by Islam, J.N.
Begins with a short introduction to the relevant aspects of general
relativity. This is followed by a detailed derivation of the Wehl-Lewis-
Papapetrou form of the stationary axially symmetric metric. The Kerr and
Tomimatsu-Sato forms of the rotating interior and exterior solutions of the
Einstein equations are then considered. Subject: physics
1985 6 X 9 122 pp. 4 diagrams
Hardback 0-521-26082-5 $47.95 (£7.99)
--------------------------------------------------------------------------
>If an EM field is somehow rotated extremely fast, shouldn't all matter be
repelled from its center? -kgo.
How fast do you want it rotated? It's fairly simple to construct a system to
produce rotating EM waves at whatever rotational velocity you wish by feeding
a pair of broadside dipole arrays with quatrature phased waves. It is quite
simple to construct a system that would have a rotational velocity of C within
the uniform field area. It might also be fairly easy to do this with a
Hemholtz coil arangement as well, but the broadside array will be much easier
to do at easily engineerable frequencies. Some really interesting paradoxes
come about when the rotational frequency is high enough so that the rotational
velocity exceeds C within the uniform field area of the arrays or within the
hemholtz coils.
-- Robert Shannon
-------------------------------------------------------------------------
Ehrenfest Paradox (Ehrenfest, 1909) --
The special relativistic "paradox" involving a rapidly rotating disc. Since
any radial segment of the disc is perpendicular to the direction of motion,
there should be no length contraction of the radius; however, since the
circumference of the disc is parallel to the direction of motion, it should
contract.
Question -- by Kung Lo (October 1995):
Take a rigid disk of radius R and spin it up to angular velocity . As seen by
an observer S that is at rest in the center of the disk, the radius is still
R, but the circumference is contracted by the Lorentz effect. How is this
possible?
More physically, if a fixed ring is just outside the spinning disk and placed
with equally spaced markers on the rim of the disk and on the fixed ring, I
know by symmetry that, when one marker on the disk is aligned with a marker on
the ring, all pairs of markers must be aligned. This contradicts the fact
that, for observer S, the distance between successive markers on the disk is
reduced by the Lorentz factor.
Answer -- provided by David Djajaputra (November 1995): It seems that the
rotating disk paradox (it turned out to be Ehrenfest's paradox) has been
extensively analyzed by many people (including Einstein himself, who developed
general relativity to answer this problem, as one author speculates...). This
I found from a nice paper :
O. Gron, "Relativistic description of a rotating disk" Am. J. Phys. V43, 869
(1975), and all the references therein.
The key sentence in Gron's paper is at the end of Section IV:
"By definition a Born rigid motion of a body leaves lenghts unchanged,
when measured in the body's proper frame . (...) A Born rigid motion is not a
material property of the body, but the result of a specific program of forces
designed to set the body in motion without introducing stresses. (...) A
transition of the disk from rest to rotational motion, while it satisfies
Born's definition of rigidity, is a kinematic impossibility"
With this kinematics the radius is R and the circumference is as measured by
observer S (lab frame), but an observer riding on the disk will measure a
distance R to the center and a distance around the circumference (he can do
this measurement by slowly walking around the spinning disk with a meter
tape). This is consistent with the usual Lorentz contraction . The point is
that this is NOT a Born rigid motion. There is much more in Gron's paper.
-- Vittorio Celli
------------------------------------------------------------------------
Several key pharases keep popping up regarding rotating fields, powerful
magnetic pulsed fields, and 90 degree cross-field phase shifts. For example,
Preston Nicholes describes a device known as a Delta T antenna in the Montauk
series of books. The Delta T antenna is described as a pyramidal structure,
but lets just take two square loops, placed at 90 degrees to each other, and
feed these two loops with an RF signal, also with a 90 degree phase shift, we
will produce a rotating magnetic field within the loops (these loops share a
common center point, and each loop is in a plane 90 degrees from the other)
The speed of rotation of this magnetic field is a direct function of the
frequancy of the applied RF signal. At the center of the antenna, the
rotational velocity is zero, but as you move out from the center, and
rotational velocity increases. At some distance from center would reach the
speed of light, dependant of the frequancy used. One could imagine that the
rotational velocity of this rotating magnetic field could reach the speed of
light within the antenna structure itself if a way could be found to make the
antenna much larger than a normaly resonant antenna would be for that same
frequancy. At several hundred megahertz, a two meter per side square loop
would have a rotational velocity well in excess of the speed of light within
the antenna structure itself.
What effect would there be at the boundry where the rotational velocity
reached, and then exceeded the speed of light. How could the magnetic field
even propogate to the center of the antenna structure if it would have to move
faster than light to reach that space? If hemholtz coils were used instead of
loops, the magnetic field strength would be uniform inside the structure, how
could the field strenght be uniform if there is not sufficient time for the
field to propogate through the space inside the structure itself?
Could such an effect actually generate a wormhole like phenomena, at energy
levels far below that of neutron stars and such? As the causal mechanism, the
magnetic field, is in roation, would this describe a traversable worm hole as
has been postulated in relationship to rotating black holes?
-- Robert Shannon
--------------------------------------------------------------------------
Aono, Osamu, 1937-
Rotation of a magnetic field / Osamu Aono and Ryo Sugihara. Nagoya, Japan :
Institute of Plasma Physics, Nagoya University, 1986. 6 p. ; 30 cm. LC CALL
NUMBER: QC717.6 .N35 no. 792 (ALTERNATE CLASS QC754.2.M3) SUBJECTS: Magnetic
fields. Electrodynamics. Research report (Nagoya Daigaku. Purazumu Kenkyujo) ;
IPPJ-792.
--------------------------------------------------------------------------
Let me clear this up a bit, the two coils are acting as antenne already,
producing the rotating field by vector sumnation of the radiated quatrature
phased EM waves. The loops would be operating as the driven elements of a
cubical antenne, not as coils as such. If you prefer, substitute the two loop
antenne with a pair of crossed dipoles at 90 degrees, this will also produce
the rotating field, but the center will be occupied by the dipoles rather than
be open as with loop antenne of by using sets of broadside arrays. Note that
this is not the same as the rotational speed reaching c inside the "uniform
field" area, as described earlier. It's simple a tool to understsand the
generation of the rotating field and the relationship between applied
frequency and the resultant roational speed. Rather than loop elements, in
practice you might use a phased array of dipole elements that produces a
constant phase plane wave, not unlike a pair of hemholtz coils produced a
uniform field within the coil sets. Four of these "broadside arrays" would
from the four sides of a cube, inside of which you could induce the fast
rotating fields from the radiated EM waves. In all cases, the driven elements
are lauching EM waves a c. Only the vector sum of the two (of four) quatrature
fields is in rotation, which leads us back the the question of what happens as
the rotational velocity of the sum of these EM fields reaches c within the
field generator, and there is not sufficient time for the fields to propogate
accross the Vr=c boundry?
This is the point where two different physists have tried to lead me dowm the
garden path of "red shifted magnetic fields". I'm not sure I'm ready to buy
that concept just yet.
-- Robert Shannon
---------------------------------------------------------------------------
GENERAL RELATIVITY & QUANTUM COSMOLOGY, ABSTRACT GR-QC/9601034
From: Tevian Dray tevian@MATH.ORST.EDU
Date: Mon, 22 Jan 1996 10:57:03 PST
The Rotating Quantum Vacuum
Author(s): Paul C. W. Davies , Tevian Dray , Corinne A. Manogue Report-no: ADP
95-43/M36 (University of Adelaide)
We derive conditions for rotating particle detectors to respond in a variety
of bounded spacetimes and compare the results with the folklore that particle
detectors do not respond in the vacuum state appropriate to their motion.
Applications involving possible violations of the second law of thermodynamics
are briefly addressed.
---------------------------------------------------------------------------
I'm also saying that a pair of crossed coils will start behaving differently
when the driving frequency is so high that the field lines near them try to
exceed the speed of light. At low frequencies the coils create a rotating
magnetic field. At high frequencies they send out radio waves having a
rotating field vector (circularly polarized waves, in other words.) WITHIN the
volume of the coils the fields still rotate, at least until the frequency is
raised so high that the coils are many wavelengths across. At these
frequencies the fields in the center of the crossed coils would be of complex
shape, maybe some kind of contracting spiral. (Which is interesting, because
at very high frequencies there would be a "hot spot" at the exact center of
the crossed coils.)
-- Robert Shannon
-------------------------------------------------------------------------
On similar topic: anyone ever heard of the "CFA antenna" flap in the UK? CFA
is for "crossed-field antenna." There were a bunch of articles and letters to
the editor in EWW, "Electronics and Wireless World," the British engineering
mag. The CFA-believers though they had discovered a way to make 1-foot
antennas which were efficient at 100-meter wavelengths. The key to the CFA was
to create the e- and b-fields separately: feed both a coil-loop and a pair of
capacitor-spheres with separate high-current and high-voltage signals
respectively, orient them 90deg to produce a broadside wave, shift the phases
with L/C networks to form the proper EM wave (90? zero? (grin), and then
obtain a powerful EM emission from a tiny antenna. There was a great quantity
of argument and name-calling over this, all done in slow-motion over many
months of letters in the letters-to-the-editor column. Then it just died away.
Either the pro-CFA side couldn't prove that it worked, or nobody believed the
proof they did find.
-- William Beaty
Go to the Next RS EG Refs. Page
Return to the RS EG Refs. Page
Go to earthquake WARNING research homepage.