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DGoncz@replikon.net
Jan24-09, 06:00 AM
Could a more detailed understanding of the replusive Casimir force
measured recently showing good agreement with theory enlighten the
theory that single bubble sonoluminescence (SBSL) derives from a
dynamic Casimir force?

The conditions for the replusive force are

e1 < e2 < e3

where e is the dielectric constant and 1, 2, and 3 are a plate, a
liquid, and an opposing plate very close to plate 1.

The surest argument I see to assert there is no relation between the
replusive Casimir force and SBSL is simply "There is no plate 1 in a
bubble", but I don't see all that well. :)

I recall from an aging Optics text I still have that when total
internal reflection (TIR) is present in a configuration of matter,
there are "evanescent waves" on the far side of the rare medium, where
we would expect none using particle theory of light. I worked out in
1997 the effective cavity gain (Q) of a dense bubble in a rare medium,
and believed at the time the vapor/gas mix inside an SBSL bubble could
"cross over" from a refractive index less than the surrounding water,
to one which is greater.

The conditions for dynamic Casimir forces are relativistic, I think,
and in any case I don't understand much when I read papers about such
forces.

Perhaps one of you would start by outlining the similarities and
differences between attractive, replusive, and dynamic Casimir-
Lipschitz forces.

Referencing:

http://www.nature.com/nature/journal/v457/n7226/abs/nature07610.html

Letter
Nature 457, 170-173 (8 January 2009) | doi:10.1038/nature07610;
Received 6 August 2008; Accepted 30 October 2008

Measured long-range repulsive Casimir=96Lifshitz forces
J. N. Munday, Federico Capasso & V. Adrian Parsegian

In which we read, in the Abstract:

".... Here we show experimentally that, in accord with theoretical
prediction12, the sign of the force can be changed from attractive to
repulsive by suitable choice of interacting materials immersed in a
fluid. ...."

Doug Goncz
Replikon Research
Seven Corners, VA 22044-0394

Richard D. Saam
Jan30-09, 06:00 AM
DGoncz@replikon.net wrote:
> Could a more detailed understanding of the replusive Casimir force
> measured recently showing good agreement with theory enlighten the
> theory that single bubble sonoluminescence (SBSL) derives from a
> dynamic Casimir force?
>
> The conditions for the replusive force are
>
> e1 < e2 < e3
>
> where e is the dielectric constant and 1, 2, and 3 are a plate, a
> liquid, and an opposing plate very close to plate 1.
>
> The surest argument I see to assert there is no relation between the
> replusive Casimir force and SBSL is simply "There is no plate 1 in a
> bubble", but I don't see all that well. :)
>
> I recall from an aging Optics text I still have that when total
> internal reflection (TIR) is present in a configuration of matter,
> there are "evanescent waves" on the far side of the rare medium, where
> we would expect none using particle theory of light. I worked out in
> 1997 the effective cavity gain (Q) of a dense bubble in a rare medium,
> and believed at the time the vapor/gas mix inside an SBSL bubble could
> "cross over" from a refractive index less than the surrounding water,
> to one which is greater.
>
> The conditions for dynamic Casimir forces are relativistic, I think,
> and in any case I don't understand much when I read papers about such
> forces.
>
> Perhaps one of you would start by outlining the similarities and
> differences between attractive, replusive, and dynamic Casimir-
> Lipschitz forces.
>
> Referencing:
>
> http://www.nature.com/nature/journal/v457/n7226/abs/nature07610.html
>
> Letter
> Nature 457, 170-173 (8 January 2009) | doi:10.1038/nature07610;
> Received 6 August 2008; Accepted 30 October 2008
>
> Measured long-range repulsive Casimir=96Lifshitz forces
> J. N. Munday, Federico Capasso & V. Adrian Parsegian
>
> In which we read, in the Abstract:
>
> ".... Here we show experimentally that, in accord with theoretical
> prediction12, the sign of the force can be changed from attractive to
> repulsive by suitable choice of interacting materials immersed in a
> fluid. ...."
>
> Doug Goncz
> Replikon Research
> Seven Corners, VA 22044-0394
>

Ref:
Peter W. Milonni,
The Quantum Vacuum,
An Introduction to Quantum Electrodynamics,
Academic Press, New York, 1994.

Pages 222 - 228

The equations describe the possibility of Casimir repulsive or
attractive force.

Although graphical basis for equations (Figure 7.1 page 222)
describes e1, e3 & e2
for two slabs e1 and e2
separated by e3.

This appears different than:
> where e is the dielectric constant and 1, 2, and 3 are a plate, a
> liquid, and an opposing plate very close to plate 1.

Richard D. Saam