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The Universe Within 12.5 Light Years

(www.atlasoftheuniverse.com)
266 points algorithmista | 2 comments | 05 Sep 25 22:20 UTC | HN request time: 0.001s | source
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stephc_int13 ◴[06 Sep 25 01:21 UTC] No.45145686[source]▶
When the Fermi Paradox was first posited, scientists and engineers seemed to believe that interstellar travel was soon to be technologically achievable, a few decades, maybe centuries for the less optimistic. Progress around space propulsion has kind of stalled since then and we should maybe question the possibility of interstellar travel as this would give an easy but unpleasant answer to the famous paradox.
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BobbyTables2 ◴[06 Sep 25 01:42 UTC] No.45145814[source]▶
I’ve always wondered — magnetism seems kinda crazy — how are two objects not touching but exerting a force(?). Practically witchcraft…

Without electricity, how well would we understand it? Just that some mysterious rocks that stick?

Wonder if one day in the distant future we’ll discover a new force we never imagined.

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lIl-IIIl ◴[06 Sep 25 07:23 UTC] No.45147314[source]▶
You might find this video of Feyman talking about magnets interesting: https://www.youtube.com/watch?v=MO0r930Sn_8
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1. BobbyTables2 ◴[06 Sep 25 21:17 UTC] No.45152919[source]▶
That is interesting. Have read his books but never seen videos.

What I was trying to get at is I argue that historically we had no reason to assume magnets to exist until we discovered them. (Sure, today we can explain them in terms of the effects of electrons traveling at relativistic speeds.)

It otherwise seems a safe assumption that we cannot move into a 4th spatial dimension (even if such exists) or do many other outlandish things. I don’t think we can prove them impossible but likely just don’t know how.

But imagine if Newton had been shown an electromagnet and asked to explain it… It would have been witchcraft!

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2. lIl-IIIl ◴[08 Sep 25 05:31 UTC] No.45164914[source]▶
He was familiar with attraction and repulsion of bodies due to static electric charge, which he attributed to "most subtle spirit": https://link.springer.com/chapter/10.1007/978-94-009-7715-0_...