Water burns!
 

Mike Kaliski wrote:
Clearly some things do appear to travel faster than the speed of light in a
vacuum. The jury appears to be out as to whether any practical use can be
made of the phenomenon.

A few centuries ago, the jury was out on whether any practical
use could be made of RF waves. The people who seem to know
what it is possible to know remind me of the patent office
employee who asserted (100+ years ago) that all possible
inventions had already been invented.
--
73, Cecil http://www.w5dxp.com

Water burns!
 

snip
In 1993, the most solid experimental evidence came from Chiao and his
colleagues Aephraim Steinberg and Paul Kwiat at the University of
California
at Berkeley. Using the Hong-Ou-Mandel interferometer ... they were able
to
measure the tunneling times of visible light. According to Brown, "the
researchers found that the photons that tunneled their way through the
optical filter arrived 1.5 femtoseconds sooner than the ones that
traveled
through air. The tunneling photons seemed to have traveled at 1.7 times
the
speed of light" ...
Similar experiments by Ferenc Krauss et al at the Technical University
in
Vienna in October of 1994 "strongly suggest that as they progressively
increased the thickness of the barrier the tunneling time saturated
toward a
maximum value" ...
snip

This was in "evanescent mode", in other words, waveguide or something
similar. Not "free space". So very very very unlikely exceeding the
speed of light in a vacuum. As in it didn't. No laws were broken.

tom
K0TAR

Tom,

The speed of light in air is not vastly different from the speed of light in
a vacuum. If photons were apparently travelling at 1.7 times the speed of
light in air, they clearly must have been exceeding the speed of light in a
vacuum.

This result was observed using visible light. Current theory is usually
quoted as nothing can travel faster than the speed of light in a vaccum. It
is probably more correct to state that objects with mass cannot exceed the
speed of light in a vacuum. Photons, having no mass, are not necessarily
subject to this rule and seem to be observed travelling at superluminal
velocity under certain very specific conditions. If the photons are
tunnelling and travelling faster than light in a vacuum, it does not
necessarily mean that any laws have been broken.

One way of imagining a way in which this could happen is if a block of
material is energised to a high energy state. Photons are continually fired
into the material and are absorbed one by one with atoms within the
structure absorbing each new photon. At some point, the material becomes
completely saturated and cannot absorb any more photons. When the next
photon hits and is absorbed, a shockwave propogates through the material and
a photon is emitted from the opposite side travelling at the same speed and
in the same direction as the original absorbed photon. Stability is restored
and energy is conserved.

But, it is the shockwave that has propogated faster than the speed of light
and it is not the original photon that entered the material that is emitted.
The emitted photon will contain exactly the same properties as the absorbed
photon and the two would be indistinguishable. So the photon appears to have
been transmitted through the material at faster than light speed, but no
laws have been broken.

A Newtons cradle can help with visualising how this can happen.

Mike G0ULI

Water burns!
 

Tom Ring wrote:
This was in "evanescent mode", in other words, waveguide or something
similar. Not "free space". So very very very unlikely exceeding the
speed of light in a vacuum. As in it didn't. No laws were broken.

What will happen when the very concept of time
is discredited as merely a human illusion?
--
73, Cecil http://www.w5dxp.com

Water burns!
 

Mike Kaliski wrote:


Tom,

The speed of light in air is not vastly different from the speed of light in
a vacuum. If photons were apparently travelling at 1.7 times the speed of
light in air, they clearly must have been exceeding the speed of light in a
vacuum.

This result was observed using visible light. Current theory is usually
quoted as nothing can travel faster than the speed of light in a vaccum. It
is probably more correct to state that objects with mass cannot exceed the
speed of light in a vacuum. Photons, having no mass, are not necessarily
subject to this rule and seem to be observed travelling at superluminal
velocity under certain very specific conditions. If the photons are
tunnelling and travelling faster than light in a vacuum, it does not
necessarily mean that any laws have been broken.

One way of imagining a way in which this could happen is if a block of
material is energised to a high energy state. Photons are continually fired
into the material and are absorbed one by one with atoms within the
structure absorbing each new photon. At some point, the material becomes
completely saturated and cannot absorb any more photons. When the next
photon hits and is absorbed, a shockwave propogates through the material and
a photon is emitted from the opposite side travelling at the same speed and
in the same direction as the original absorbed photon. Stability is restored
and energy is conserved.

But, it is the shockwave that has propogated faster than the speed of light
and it is not the original photon that entered the material that is emitted.
The emitted photon will contain exactly the same properties as the absorbed
photon and the two would be indistinguishable. So the photon appears to have
been transmitted through the material at faster than light speed, but no
laws have been broken.

A Newtons cradle can help with visualising how this can happen.

Mike G0ULI


Mike,

You had me fooled. It appeared that you might actually know something.
But that response bent the needle on my bull**** meter.

73,
Gene
W4SZ

Water burns!
 

Mike Kaliski wrote:
snip
In 1993, the most solid experimental evidence came from Chiao and his
colleagues Aephraim Steinberg and Paul Kwiat at the University of
California
at Berkeley. Using the Hong-Ou-Mandel interferometer ... they were able
to
measure the tunneling times of visible light. According to Brown, "the
researchers found that the photons that tunneled their way through the
optical filter arrived 1.5 femtoseconds sooner than the ones that
traveled
through air. The tunneling photons seemed to have traveled at 1.7 times
the
speed of light" ...
Similar experiments by Ferenc Krauss et al at the Technical University
in
Vienna in October of 1994 "strongly suggest that as they progressively
increased the thickness of the barrier the tunneling time saturated
toward a
maximum value" ...
snip

This was in "evanescent mode", in other words, waveguide or something
similar. Not "free space". So very very very unlikely exceeding the
speed of light in a vacuum. As in it didn't. No laws were broken.

tom
K0TAR

Tom,

The speed of light in air is not vastly different from the speed of light in
a vacuum. If photons were apparently travelling at 1.7 times the speed of
light in air, they clearly must have been exceeding the speed of light in a
vacuum.

This result was observed using visible light. Current theory is usually
quoted as nothing can travel faster than the speed of light in a vaccum. It
is probably more correct to state that objects with mass cannot exceed the
speed of light in a vacuum. Photons, having no mass, are not necessarily
subject to this rule and seem to be observed travelling at superluminal
velocity under certain very specific conditions. If the photons are
tunnelling and travelling faster than light in a vacuum, it does not
necessarily mean that any laws have been broken.

One way of imagining a way in which this could happen is if a block of
material is energised to a high energy state. Photons are continually fired
into the material and are absorbed one by one with atoms within the
structure absorbing each new photon. At some point, the material becomes
completely saturated and cannot absorb any more photons. When the next
photon hits and is absorbed, a shockwave propogates through the material and
a photon is emitted from the opposite side travelling at the same speed and
in the same direction as the original absorbed photon. Stability is restored
and energy is conserved.

But, it is the shockwave that has propogated faster than the speed of light
and it is not the original photon that entered the material that is emitted.
The emitted photon will contain exactly the same properties as the absorbed
photon and the two would be indistinguishable. So the photon appears to have
been transmitted through the material at faster than light speed, but no
laws have been broken.

A Newtons cradle can help with visualising how this can happen.

Mike G0ULI




Keep smoking, it must be good stuff.

tom
K0TAR

Water burns!
 

Cecil Moore wrote:
Jimmie D wrote:
the problem isnt with believing space can be empty but believing that
space is nothing..

Empty and nothing are synonyms.

And yet say very different things. The difference is important in some
(most?) cases. Which means they really are not synonyms.

tom
K0TAR

Water burns!
 

"Gene Fuller" wrote in message
...
Mike Kaliski wrote:


Tom,

The speed of light in air is not vastly different from the speed of
light in
a vacuum. If photons were apparently travelling at 1.7 times the speed
of
light in air, they clearly must have been exceeding the speed of light
in a
vacuum.

This result was observed using visible light. Current theory is usually
quoted as nothing can travel faster than the speed of light in a vaccum.
It
is probably more correct to state that objects with mass cannot exceed
the
speed of light in a vacuum. Photons, having no mass, are not necessarily
subject to this rule and seem to be observed travelling at superluminal
velocity under certain very specific conditions. If the photons are
tunnelling and travelling faster than light in a vacuum, it does not
necessarily mean that any laws have been broken.

One way of imagining a way in which this could happen is if a block of
material is energised to a high energy state. Photons are continually
fired
into the material and are absorbed one by one with atoms within the
structure absorbing each new photon. At some point, the material becomes
completely saturated and cannot absorb any more photons. When the next
photon hits and is absorbed, a shockwave propogates through the material
and
a photon is emitted from the opposite side travelling at the same speed
and
in the same direction as the original absorbed photon. Stability is
restored
and energy is conserved.

But, it is the shockwave that has propogated faster than the speed of
light
and it is not the original photon that entered the material that is
emitted.
The emitted photon will contain exactly the same properties as the
absorbed
photon and the two would be indistinguishable. So the photon appears to
have
been transmitted through the material at faster than light speed, but no
laws have been broken.

A Newtons cradle can help with visualising how this can happen.

Mike G0ULI


Mike,

You had me fooled. It appeared that you might actually know something.
But that response bent the needle on my bull**** meter.

73,
Gene
W4SZ

Gene

I don't claim that this is what does happen, merely propose it as an aid to
visualising how the observed results could possibly arise without
necessarily violating any of the currently accepted laws of physics. Clearly
the experimental results demonstrate something odd is happening in the
laboratory and photons are apparently exceeding light speed, which they
shouldn't be able to do in light of current knowledge.

I think it must have been a mention of Newton together with quantum
phenomena that upsets people :-)

Regards

Mike G0ULI

Water burns!
 

Tom Ring wrote:
Cecil Moore wrote:
Empty and nothing are synonyms.

And yet say very different things. The difference is important in some
(most?) cases. Which means they really are not synonyms.

From Webster's: "empty - containing nothing"
I guess it depends upon the definition of nothing.
Seems to me, absolute-nothing cannot exist within
our universe.
--
73, Cecil http://www.w5dxp.com

Water burns!
 

Cecil Moore wrote:

...
After all, it took ~250,000 years for us to figure
out how to modulate EM waves.

John Smith imagines a caveman shading a fire (newly developed
technology) with a palm frond, jumping in glee, pointing, and declaring,
"Look, I am modulating light! I just wonder what I can do with a
campfire and a blanket?"

And then, I return to work ... and thoughts of cavemen leave ...

Regards,
JS

Water burns!
 

On Tue, 12 Jun 2007 02:34:10 GMT, Gene Fuller
wrote:



A Newtons cradle can help with visualising how this can happen.

Mike G0ULI


Mike,

You had me fooled. It appeared that you might actually know something.
But that response bent the needle on my bull**** meter.

73,
Gene
W4SZ

FWIW:

http://www.lhup.edu/~dsimanek/scenario/cradle.htm

John Ferrell W8CCW
"Life is easier if you learn to
plow around the stumps"