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A Dyson sphere around a black hole

(arxiv.org)
214 points SkyMarshal | 3 comments | 19 Aug 21 03:40 UTC | HN request time: 0.749s | source
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sydthrowaway ◴[19 Aug 21 05:47 UTC] No.28230748[source]▶
Why do we think Dyson spheres exist. It's completely conjecture.
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dheera ◴[19 Aug 21 06:21 UTC] No.28230941[source]▶
Yes. Also, conservation of energy is completely conjecture.

Personally I think it will ultimately prove out to not be true in all cases. I might sound like a heretic for saying this and would be berated in the scientific community for saying that, but in the past most laws that establish constraints eventually prove out to be only true under certain controlled environments.

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1. nabla9 ◴[19 Aug 21 06:41 UTC] No.28231058[source]▶
You are late to the game and behind scientific community.

Physicists knows the exact reason why energy is conserved and why it might not be conserved. Conserved quantities arise from symmetries in variational systems. Conservation laws are consequence, not unexplained axiomatic law.

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2. dheera ◴[19 Aug 21 07:41 UTC] No.28231374[source]▶
No, they don't "know".

Those symmetries are not shown to be universally true, they are just what we have been able to observe, much like Newton's laws are based on observations on the Earth only.

Yet Einstein showed that they are only a special case of a much more general universe.

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3. nabla9 ◴[19 Aug 21 09:39 UTC] No.28231946[source]▶
It's possible that you didn't read my comment carefully enough.

I wrote: "Physicists knows the exact reason why energy is conserved and why it might not be conserved."

To parse it:

1. exact reason why energy is conserved

2. why it might not be conserved.