I am having problems wrap around why you can't send information faster than light with a similar setup to the quantum eraser experiment. ( https://arxiv.org/abs/quant-ph/9903047v1 )
What I mean is, isn't the fact of whether I measured the photon or not, some sort of information? If it is not interfering, that means I've measured it, if it is, i didn't. Since this will happen instantaneously, I can send information by measuring or not within some fixed time-steps and then observing the pattern on the screen on the other side.
I am sure this is impossible and there are good reasons for it, but I don't know what they are. Thanks for explaining. Also, if that can be done without too much specialistic physics lingo, that would be great. I am an electronics engineer (hence the question) and the farthest I got in modern physics was special relativity. Thank you!
(Edit): I am not sure I asked this correctly, what I meant was, could the interference pattern itself or its absence be considered a hidden variable?
In my understanding, the paper focuses on proving that knowing which path is not a hidden variable (Bell's inequalities), but it doesn't say anything about the collapse of the wave function. Is a wave function collapse a hidden variable? Maybe paper doesn't explain this because it is a stupid question that makes no sense to people that know the experiment...
But if it does, then this is a time-machine!