Only faster than c wave packets would be transmitted. I didn't mean to
imply both slower and faster wave packets would be transmitted.
Harry
On Tue, May 21, 2019, 12:21 PM Kevin O'Malley If time is determined by the speed of light, how would you determine
> which packets were generated first? Would they be going by some other
> limiting speed agent other than C?
>
> On 5/12/19, H LV wrote:
> > If one can build a transmitter and a receiver to transmit and detect wave
> > packets travelling with sub c group velocity why can't one do the same
> for
> > wave packets with group velocity much greater than c and achieve
> > communication which is much faster than c?
> > Harry
> >
> > On Fri, May 3, 2019, 11:51 PM Axil Axil >
> >>
> >>
> >> It should be noted that while Einstein's theory of special relativity
> >> prevents (real) mass, energy, or information from traveling faster than
> >> the
> >> speed of light c (Lorentz et al. 1952, Brillouin and Sommerfeld 1960,
> >> Born
> >> and Wolf 1999, Landau and Lifschitz 1997), there is nothing preventing
> >> "apparent" motion faster than c (or, in fact, with negative speeds,
> >> implying arrival at a destination before leaving the origin). For
> >> example,
> >> the phase velocity and group velocity of a wave may exceed the speed of
> >> light, but in such cases, no energy or information actually travels
> >> faster
> >> than c. Experiments showing group velocities greater than c include that
> >> of
> >> Wang et al. (2000), who produced a laser pulse in atomic cesium gas with
> >> a
> >> group velocity of -310c. In each case, the observed superluminal
> >> propagation is not at odds with causality, and is instead a consequence
> >> of
> >> classical interference between its constituent frequency components in a
> >> region of anomalous dispersion (Wang et al. 2000).
> >>
> >> Keith Fredericks has an opinion that strange radiation is a tachyon.
> This
> >> SR quasiparticle might be tachyonic is that it is most likely based on
> >> the
> >> polariton. The polariton does generate superluminal light in the form of
> >> x-waves.
> >>
> >> https://www.nature.com/articles/lsa2017119
> >>
> >> Superluminal X-waves in a polariton quantum fluid
> >>
> >> This article shows that a polariton can naturally produce superluminal
> >> light (X-waves) when excited with a pulsed laser.
> >>
> >> This unexpected behavior of light may explain how Strange radiation (SR)
> >> can be considered a tachyon, a superluminal particle.
> >>
> >>
> >
>
>
