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The sun you see right now exploded 7 minutes ago and you'd have no way of knowing. You'd still feel its warmth. Still see it in the sky. Still orbit it. For 8 minutes and 20 seconds, you'd live in a universe that no longer has a sun and have absolutely no way to detect the difference.
This is because gravity also travels at the speed of light. If the sun vanished, Earth would continue orbiting the empty space where it used to be for the same 8 minutes and 20 seconds. Einstein proved this. The gravitational wave carrying the information "the sun is gone" propagates at exactly c. Light, gravity, and information all share the same speed limit.
Now scale the paradox in this post. 90 light-years is nothing. The Andromeda galaxy is 2.5 million light-years away. Every photograph of it is a 2.5 million year old snapshot. The entire galaxy could have collided with something catastrophic 2 million years ago. We'll find out 500,000 years from now.
The James Webb Space Telescope routinely photographs galaxies from 13.4 billion years ago. Those galaxies no longer exist in any form we'd recognize. The stars burned out. The civilizations, if any, rose and fell billions of years before Earth formed. Webb is photographing ghosts.
The deepest implication: "right now" is a local phenomenon. It exists only in the space you can physically touch. Beyond that, everything you see, measure, or interact with is a time-delayed recording. The further you look, the older the recording gets. There is no method, even in principle, to know the current state of anything beyond your immediate surroundings.
The entire observable universe is a 13.8 billion year old museum where every exhibit is labeled with a different date and nothing is current.
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