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embedding-shapetoday at 9:07 AM1 replyview on HN

> a ray of light has to know where it will ultimately end up before it can choose the direction to begin moving in

I'm no physicists, so I guess I'll ask it: Why?

Also related, why do some ray of light then "see" a black hole yet decide to head into them anyways, if they saw it before they went in that direction? Seems like a dumb move :)


Replies

lloekitoday at 10:01 AM

Its future isn't over there because it moves in that direction, instead it moves in that direction because its future lies over there.

Relatedly:

> [General Relativity] basically says that the reason you are sticking to the floor right now is that the shortest distance between today and tomorrow is through the center of the Earth.

https://physics.stackexchange.com/questions/250800/gr-and-my...