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by pjbeam 1785 days ago
If two different x can produce the same y information is lost on the hash transformation. Finding _an x_ for your y is not the same as finding _the x_. That said, Laplace's Demon is, well, a demon. Presumably the devil can get the demon to unspool time to see what the input was and the math doesn't matter, collisions or not.
2 comments
Sebb767 1785 days ago
> Finding _an x_ for your y is not the same as finding _the x_.

Not in all cases, but in the case of NFTs and other cryptocurrencies, it is. If a second private key fulfills all constraints of the original one (like size and all computed results so far), it is functionally equivalent to the original one.

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ithinkso 1785 days ago
In cryptography either you only need 'an x', in cases that the original x does not matter, or if it does, then you can just as easily find all x of size less than large enough N and find 'the x', it is still solely restricted by time.

Laplace's demon, information loss, Landauer's principle etc. are at most tangentially related to the problem discussed

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pjbeam 1785 days ago
You understand that isn't the same mathematically as reversing the hash? If you farm the set of all possible x and try them to see what works you do not have an inverse function in your hands.
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ithinkso 1785 days ago
> If you farm the set of all possible x and try them to see what works you do not have an inverse function in your hands.

I'm not sure I follow, what do I have then? Could you give me an example?

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