# Why can't light travel three days into the future then transmit that information back to us prior to us arriving at that position? [closed]

Example: If a football game between the Pittsburgh Steelers @ Tennessee Titans will happen in 3 days Sunday 10/25/2020 at 1pm, why can't light leave today 10/22/2020 and go to where the Earth will be on Sunday and transmit that information back to an observer prior to them arriving at the location on Sunday?

This is an example of my question. I realize there is more to information transmitting. But, why can't light go to the future and transmit back in the simplest of senses prior to us arriving to that location? In my estimation light can travel 3 days into the future and back rather quickly. We know where the earth will be in exactly 72 hours. The math works out for light to be able to do this. What am i missing? Thank you.

• Why do you assume light could do anything like that? In every physical frame of reference light travels only into the future (well, apart from strange constructs in general relativity, which as of now seem to have little to do with our physical reality).
– drfk
Oct 22, 2020 at 16:19
• Can you expand on what you mean by, "in every physical frame of reference light travels only into the future." is it impossible for us to send a light signal into a future location of the earth. I mean don't we know the exact location the earth will be at in 3 days? Does light not have this capability? Thanks for responding. Oct 22, 2020 at 16:40
• I think it is possible (in principle) to send light to the future location of earth. However, it would be hard, since light travels in 8min to the sun and earth doesn't travel that distance even in three days, so you would have to build a huge contraption of mirrors or something alike to get the light to that position in three days... However my point was simply, you seem to assume light can travel backwards in time, but it cannot.
– drfk
Oct 22, 2020 at 16:54
• In my thought experiment i would want the light to get to the position as fast as it can, but i guess i don't understand why it can't reflect back from that position? Is that considered backwards in time? Because isn't it really reflecting back to our future state? Im not asking it to go to yesterday or 2 weeks ago. Im asking it to go to our future. Thank you, im obviously confused with how this works. These conversations help. Oct 22, 2020 at 17:07
• How are you sending light backwards in time? Oct 22, 2020 at 17:26