superluminal possibility

Various experiments over the years
have verified that no information travels faster than light
as appears to be the case in regards to recently negated experimental
superluminal neutrino OPERA results.

In astrophysics, Blazar apparent superluminal jets are presently
explained by difference in geometry of Jet vector and observer.

But National Institute of Standards and Technology work as reference:
arXiv:1204.0810v1 [quant-ph] 3 Apr 2012
suggests that superluminal transfer of information is possible
as per their suggestion:

"the present results suggest
that the superluminal propagation of images may be possible
in future experiments."

Could some astrophysical data
particularly regarding some Blazar superluminal jets
be explained in this context?

In article , "Richard D. Saam"
writes:

Various experiments over the years
have verified that no information travels faster than light
as appears to be the case in regards to recently negated experimental
superluminal neutrino OPERA results.

Right.

In astrophysics, Blazar apparent superluminal jets are presently
explained by difference in geometry of Jet vector and observer.

Right.

But National Institute of Standards and Technology work as reference:
arXiv:1204.0810v1 [quant-ph] 3 Apr 2012
suggests that superluminal transfer of information is possible
as per their suggestion:

"the present results suggest
that the superluminal propagation of images may be possible
in future experiments."

Could some astrophysical data
particularly regarding some Blazar superluminal jets
be explained in this context?

No. Their conclusion you quote, if taken at face value, seems to imply
the propagation of information at speeds faster than light. If so, this
would be a sensation. (I doubt this is what they mean, though.)
However, it has nothing to do with blazars. You seem to be taking two
things which have one thing vaguely in common and postulating a
connection for which there is no evidence.

On 4/14/12 4/14/12 5:28 AM, Richard D. Saam wrote:
But National Institute of Standards and Technology work as reference:
arXiv:1204.0810v1 [quant-ph] 3 Apr 2012
suggests that superluminal transfer of information is possible

This looks like anomalous dispersion in a new guise. As long as any individual
wave is restricted to speeds = c, even though a superluminal group velocity is
possible, no information propagates faster than c -- the front velocity remains
= c. The superluminal propagation of pulses is merely an artifact of the way
the different waves interfere with each other, but there is no pulse if there
are no waves, and if the individual waves travel = c so does the front edge of
the waves, the forward limit of the pulse, and any information transfer.

See a direct demonstration of this (Java required):
http://gregegan.customer.netspace.ne...ETS/20/20.html
Note how closing and then opening the shutter affects the waves. Note that a
NEGATIVE group velocity is possible, showing how artificial are these group
velocities, and that they do NOT represent any transfer of information; the
paper referenced above mentions a negative pulse velocity, implying they are
discussing a similar interference phenomenon.


Tom Roberts

On 4/14/12 9:43 AM, Phillip Helbig---undress to reply wrote:
In , "Richard D. Saam"
But National Institute of Standards and Technology work as reference:
arXiv:1204.0810v1 [quant-ph] 3 Apr 2012
suggests that superluminal transfer of information is possible
as per their suggestion:

"the present results suggest
that the superluminal propagation of images may be possible
in future experiments."

Could some astrophysical data
particularly regarding some Blazar superluminal jets
be explained in this context?

No. Their conclusion you quote, if taken at face value, seems to imply
the propagation of information at speeds faster than light. If so, this
would be a sensation. (I doubt this is what they mean, though.)
However, it has nothing to do with blazars. You seem to be taking two
things which have one thing vaguely in common and postulating a
connection for which there is no evidence.

Their superluminal information propagation statement is based on
"multi-spatial-mode nature of 4wave mixing (WM) in atomic vapors",
which appears to be an extrapolation of the reported experimental
results based on solid rubidium (Rb) cell.
In as much as blazars may have an "atomic vapor" component,
the connection may be valid.

I can appreciate Tom Robert's animation in this regard,
but there must be something about the 'atomic vapor' medium that may
extend this NIST fast light concept to superluminal transfer of
information possibility.

Richard D. Saam