[extropy-chat] SETI: First radio signal from alien

[scerir]

Mike Lorrey 

> it might be an example of an entangled photon 
> FTL comm device, that it instantaneously senses
> when someone is listening and starts shifting 
> its freq then. 

de Broglie wavelenght of a bi-photon (2 entangled
photons) is 1/2 of the usual de Broglie wavelenght
of an individual photon. Penta-photons are produced
in laboratories, to date.

But this is not enough to modulate. You need
another entanglement between a n-photon current 
at the source and a n-photon current at the 
detector (earth). "n" variable too! ???

Another possibility is a sort of triangular
entanglement between a photon (at the source)
and a bi-photon, going to a detector (earth).
Measurements performed (or not performed) on 
the photon at the source could dis-entangle the 
bi-photon going to the detector (earth), 
changing its wavelenght. ???

A double Franson-type "time" interferometer
(one interferometer on the star, one on the earth)
could, in principle, be useful, since the outcomes
in both interferometer are the same (if delta phases
= zero), with entangled photons. Possibility of 
red/blue shifting modulation ????

Another (crazy, eh!) one. If two sources send signals
(same wavelenght, more or less, the "same" wavelenght 
is not a "must") to earth, and the geometry is such 
that you can not distinguish wich of the two sources 
emitted that signal (photon), you get (in theory) a 
double strange effect: interference of signals (one 
photon two sources interference) and entanglement 
between the sources (if they are quantal!). Now if 
the sources are, then, entangled .... could they .... 
bah!

But yes, Star Trek physics can do much better than
this.