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That's Just Rhetoric

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Posted by Rich on December 20, 2000 21:41:43 UTC

We do not see the Andromeda Galaxy as it was 2 million years ago. We see the light it made 2 million years ago. The light we see is the light that is visual to us as of now.
Suppose you are on Earth and the Andromeda galaxy hasn't formed yet. You look into the sky and see nothing. Then the galaxy forms and finally two million years later, you see the galaxy's first light that has reached Earth. You never see the galaxy itself though. You just see the part that has reached us. And when the galaxy dies, for two million years you won't know it because the info hasn't arrived yet. It has happened, but you don't know it yet.
A parallel? You and I are in a room. You are going to take a seat. I play a prank and pull the seat away from you. You then sit down, unknowingly, and fall to the ground. When you hit the ground, you now know that the chair moved. But that doesn't mean that you are seeing into the past. It just means you learned something after the fact. To you the knowledge of the chair being moved happened ten seconds after I knew the chair was moved. Your knowledge is just relative. The chair was moved at the same time to both, its just when you actually knew it that changed.

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