4 ms·

I think you misunderstand. What's being described is a Phase Conjugate Mirror (PCM) -- Think of it as a mirror where the angle of incidence equals the angle o

I think you misunderstand. What's being described is a Phase Conjugate Mirror (PCM) -- Think of it as a mirror where the angle of incidence equals the angle of reflection, but without being translated into the opposite quadrant. It does not "buffer" signals incident upon it, but reflects it along a path that it took to get to the PCM. So it's the same path through space that you would get if you reversed time from the moment the signal hit the mirror. I'm sure that was clear as mud, here's a wikipedia link: https://en.wikipedia.org/wiki/Nonlinear_optics#Optical_phase_conjugation https://en.wikipedia.org/wiki/Nonlinear_optics#Optical_phase...

nielsbot 4y ago
So the photons re-trace their steps instead of continuing forward. I think the picture of the tiger seen through the distorion of a glass bottle on the linked page explains it pretty well. But I'm a layperson.
- fnordpiglet 4y ago
  No I don’t think that’s right: When a light wave enters the new time interface and the device changes its optical properties, the signal keeps moving forward in space. However, the signal gets reversed—if it were a spoken word, it would sound as if it were getting played backwards. In contrast, with a conventional reflection, a light or sound wave would travel back at its source but mostly look or sound the same as it did before the reflection. — They continue forward, but they behave in the reverse with respect to time alone.
tomxor 4y ago
I did interpret it as effectively reflecting along the same path, I was using "buffer" in a more abstract sense to compare how it would be processed digitally. But I don't doubt I've misunderstood something, my description of photons traversing the medium is probably what sounds physically inaccurate, I'm no expert in photonics and don't really know what a PCM is. As someone who does, are you able to corroborate whether the effect differs abstractly from what I described in terms of reversing the signal, as in a LIFO? Because this was my gripe with the article, the way the concept was explained makes it sounds like something more than it is.
anonymousiam 4y ago
Also referred to as a "corner cube": https://en.wikipedia.org/wiki/Corner_reflector https://en.wikipedia.org/wiki/Corner_reflector
- dtgriscom 4y ago
  Corner reflectors don't reverse the order of the incoming beam.
- retrocryptid 4y ago
  No. This is not a corner reflector. Read the wikipedia reference I posted.

nielsbot 4y ago

So the photons re-trace their steps instead of continuing forward. I think the picture of the tiger seen through the distorion of a glass bottle on the linked page explains it pretty well. But I'm a layperson.

fnordpiglet 4y ago
No I don’t think that’s right: When a light wave enters the new time interface and the device changes its optical properties, the signal keeps moving forward in space. However, the signal gets reversed—if it were a spoken word, it would sound as if it were getting played backwards. In contrast, with a conventional reflection, a light or sound wave would travel back at its source but mostly look or sound the same as it did before the reflection. — They continue forward, but they behave in the reverse with respect to time alone.

tomxor 4y ago

I did interpret it as effectively reflecting along the same path, I was using "buffer" in a more abstract sense to compare how it would be processed digitally. But I don't doubt I've misunderstood something, my description of photons traversing the medium is probably what sounds physically inaccurate, I'm no expert in photonics and don't really know what a PCM is. As someone who does, are you able to corroborate whether the effect differs abstractly from what I described in terms of reversing the signal, as in a LIFO? Because this was my gripe with the article, the way the concept was explained makes it sounds like something more than it is.

anonymousiam 4y ago

Also referred to as a "corner cube": https://en.wikipedia.org/wiki/Corner_reflector https://en.wikipedia.org/wiki/Corner_reflector

dtgriscom 4y ago
Corner reflectors don't reverse the order of the incoming beam.
retrocryptid 4y ago
No. This is not a corner reflector. Read the wikipedia reference I posted.