Re: Delayed choice experiment and interstellar signalling

On Mar 18, 2:43 am, "Williamknowsbest" <William.M...@xxxxxxxxx> wrote:

We don't need interstellar civilization to do this experiment.

No indeed, it can be done in French civilization. But it doesn't mean
you can send signals faster than light, because the light still has to
travel the distance.



Science 16 February 2007:
Vol. 315. no. 5814, pp. 966 - 968


Experimental Realization of Wheeler's Delayed-Choice Gedanken
Experiment

Vincent Jacques,1 E Wu,1,2 Frédéric Grosshans,1 François Treussart,1
Philippe Grangier,3 Alain Aspect,3 Jean-François Roch1*

Wave-particle duality is strikingly illustrated by Wheeler's delayed-
choice gedanken experiment, where the configuration of a two-path
interferometer is chosen after a single-photon pulse has entered it:
Either the interferometer is closed (that is, the two paths are
recombined) and the interference is observed, or the interferometer
remains open and the path followed by the photon is measured. We
report an almost ideal realization of that gedanken experiment with
single photons allowing unambiguous which-way measurements. The choice
between open and closed configurations, made by a quantum random
number generator, is relativistically separated from the entry of the
photon into the interferometer.

1 Laboratoire de Photonique Quantique et Moléculaire, Ecole Normale
Supérieure de Cachan, UMR CNRS 8537, 94235 Cachan, France.
2 Key Laboratory of Optical and Magnetic Resonance Spectroscopy, East
China Normal University, 200062 Shanghai, China.
3 Laboratoire Charles Fabry de l'Institut d'Optique, Campus
Polytechnique, UMR CNRS 8501, 91127 Palaiseau, France.


.

Relevant Pages

  • Re: Winds of change
    ... Hence the interferometer. ... >>with a single photon. ... >>mostly theoretical resolution of the ultraviolet catastrophe. ... A single quantum doesn't convey ...
    (sci.physics.relativity)
  • Re: Winds of change
    ... With the interferometer one can find ... >>nullpoints don't move. ... It knocks out the individual electron. ... The photon, with a longer wavelength, bounces off. ...
    (sci.physics.relativity)
  • a laymans queston about quantum physics and interference
    ... I don't know much about quantum physics so please excuse me if I use ... Mach-Zehnder interferometer, modify it by placing a photon detector in both ...
    (sci.physics)
  • Re: Quantum Paradox of a Self-Interference of a Photon in VLBI
    ... A photon point of view. ... > of an interference phenomenon in VLBI an interferometer. ... final analysis each person must make up their own mind - and physicists have ... The addition of signals is carried out in the computer, ...
    (sci.astro)
  • Re: Quantum Paradox of a Self-Interference of a Photon in VLBI
    ... A photon point of view. ... > of an interference phenomenon in VLBI an interferometer. ... final analysis each person must make up their own mind - and physicists have ... The addition of signals is carried out in the computer, ...
    (sci.physics.relativity)