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Comment by jeffwass | Hacker News Reader

>Einstein said that nuclear fission was impossible, before Fermi promptly proved him dead wrong.

Reference please.

And was this before or after the famous Einstein-Szilard letter to Roosevelt, which not only motivated the Manhattan Project but also specifically referenced Fermi's unfinished theoretical research of a possible chain reaction in uranium?

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Google found me this [1].

"On 29 December 1934, Albert Einstein was quoted in the Pittsburgh Post-Gazette as saying, “There is not the slightest indication that [nuclear energy] will ever be obtainable. It would mean that the atom would have to be shattered at will.” This followed the discovery that year by Enrico Fermi that if you bombard uranium with neutrons, the uranium atoms split up into lighter elements, releasing energy."

This would be before the 1939 letter.

[1]: https://www.newscientist.com/article/dn13556-10-impossibilit...

Do not confuse "no indication that [nuclear energy] will ever be obtainable" (there is no evidence that it is an achievable engineering feat) with "it is impossible" (it is explicitly not permitted by physics as we understand it)

You're probably right about Einstein not suggesting there was a hard physical limit preventing nuclear energy. But I don't think that hard physical limits are a good argument anyway.

There are FTL proposals that do not violate known physics, such as distorting spacetime using some perhaps yet unknown mechanism.

Saying that there are hard limits in physics here, as you did, suggests that research in this direction is not worth our time.

I believe that is misleading.

That seems way bogus to me. Fermi and the physics world believed that he had found transuranic elements. It was Hahn, Meitner and Strassman who said it was fission in late 1938 (a couple of months after Fermi got the Nobel citing that discovery, but no worries, he had done plenty of Nobel-worthy things).

> That seems way bogus to me.

I'm sorry, I'm not sure exactly which part you're objecting to?

In 1934 everybody thought that Fermi had discovered transuranic elements, that it was fission wasn't clear until Hahn and Strassman's experiment in late 1938.

If Einstein said that, I'd say he was wrong at the time, because already in the 1920s it seemed probable that nuclear fusion powers the stars: https://en.wikipedia.org/wiki/Stellar_nucleosynthesis#Histor...

Of course that's a long way from practical engineering, but it is evidence that nuclear power may be obtainable.

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