Re:In a photo of a black hole, a possible key to mysteries
by Strilanc on Friday June 05, 2020 @02:50AM
(#23425760)
Even accounting for the uncertainty principle, the amount of information you can transfer in principle with a single photon is far more than one bit. For example, you can distinguish the single photon hitting a screen at more than two different times, or at more than two different places, or at more than two different energies.
Re:In a photo of a black hole, a possible key to mysteries
by pdonis on Saturday June 06, 2020 @02:14AM
(#23437212)
> you can distinguish the single photon hitting a screen at more than two different times, or at more than two different places, or at more than two different energies.
You can't transfer information by any of these means because you can't control the time or the location or the energy of the photon hitting the screen.
The reason polarization is used to carry information in quantum computers is that you can control it, so you can use it to transfer information. But, as I said, a single photon can only be used to read out one bit in this way.
Re:In a photo of a black hole, a possible key to mysteries
by cryptonector on Saturday June 06, 2020 @02:31AM
(#23437265)
Wavelength certainly has more than one bit.
In most quantum information experiments, that observable is polarization (more precisely, polarization in some particular direction), which is an exact one-bit measurement result.
In radio telescope observations, it's typically amplitude and wavelength that are measured. I don't know that "the information content of a single photon" is really meaningful for such observations since they don't observe single photons, they observe the overall intensity at different wavelengths.