Idea for a mobile app:Alice video-calls Bob with an intentional delay of, let's say, 20 seconds; both are using smartphones and mobile data transmission through the Internet, maybe the cell network. The two devices can interact with each other using some overlayed user interface on the screen (like buttons) with which the caller can ask the second user to do a challenge with the set delayed transmission in some kind of buffer (hopefully I said that right because I'm not so tech savvy). The other user had to already have his camera recording with 20 seconds or more of anticipation, before the call, which would be the transmitted, buffered video stream.Can that be implemented in such a way that one person is sending a signal to the other person x seconds into the past, somehow, due to the transmission lag?I got this idea after watching a livestream of a Tokyo skyline scenery that I discovered was approximately delayed by 20 seconds; meaning, if I asked, via a smartphone, a hypothetical friend walking in front of a live webcam transmission with a lag measurable in seconds, in some Japanese city via a mobile messaging app like Line or Telegram (which is basically instantaneous), to do a hand gesture to the webcam whose livestream I can see on my laptop, and that person was conscious about the present moment, he or she would know I was watching them make a hand gesture x seconds ago, but he would also know I'm still watching them "right now".Hopefully I'm just posting retarded troll Physics at 12:36 A.M. and not something real that could be dangerous.
>>16928090This is pretty babblish but to sum it up, no you can't send signals to the past using a cell phone video call.I suspect you had something else in mind, try it again tomorrow.
>watch a movie that I already know the ending to>I BROKE PHYSICS
Time on a earthly scale is uniform.
what if there were 2 planets and they were 2 light years apart and I stood inbetween them with a laser pointer in each hand and turned them on at the same time and I told them earlier that I was going to do that then when one planet sees the laser pointer they know the other planet is also seeing the laser pointer if though the other planet is 2 lightyears away so it'd be impossible for them to know that in real time would the universe explode?
>>16928259Einstein said time is relative to the observer. Are you saying that line of thinking doesn't apply on Earth (assuming we live on a ball Earth floating in space)? Satellites supposedly have to adjust their clocks for time dilation in orbit.https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_Positioning_System#Relativity
