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Q&A Rigorous Science Meta
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Q&A How do we know that distant stars and galaxies are real?

In some universe,with physical laws the same as in ours, our world is some kind of "lab environment". Our solar system is enclosed in a balloon-like sphere with a radius of a few light-days around ...

4 answers  ·  posted 6y ago by Vancalar‭  ·  last activity 6y ago by Vancalar‭

Question space reality-check