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Re:The Absurdity Of Stacks by explaininjs on Sunday May 21, 2023 @08:24AM (#36020178)
It’s a joke, it’s mathematically unsolvable. Though even if it were I don’t see the connection to encryption?
Re:The Absurdity Of Stacks by ndsipa_pomu on Sunday May 21, 2023 @08:36AM (#36020256)
Sorry if I got wooshed.

It's currently unsolved, but I don't think that it's been proved to be unsolvable as surely that would prove P ≠ NP. The connection to encryption is that integer factorisation could then be solved in polynomial time which would break current systems, though in theory a much longer key length could be used to try to outpace computer power, especially if the polynomial algorithm is hugely inefficient.

Re:The Absurdity Of Stacks by explaininjs on Sunday May 21, 2023 @08:43AM (#36020317)
P/NP and Halting are entirely different concepts. I suggest reading up on the Halting problem - it’s actually very mind opening.

Edit: it wouldn’t be a stretch to call it the most important result in all of mathematics

Re:The Absurdity Of Stacks by ndsipa_pomu on Sunday May 21, 2023 @08:56AM (#36020428)
If you have a solution to the halting problem, then it would be possible to cast the P/NP problems in terms of a program and knowing whether or not it halts would allow you to determine whether P=NP.
Re:The Absurdity Of Stacks by explaininjs on Sunday May 21, 2023 @08:58AM (#36020441)
That may be, but statements that start “if false …” aren’t very useful.
Re:The Absurdity Of Stacks by sharkbot on Sunday May 21, 2023 @09:10AM (#36020525)
The halting problem has been proven definitively undecidable via proof by contradiction, by Alan Turing. The proof implicitly created the notion of Turing machines, a key model of computation.

There is a solution to the halting problem. It’s that it is undecidable.

Re:The Absurdity Of Stacks by dreamcompiler on Sunday May 21, 2023 @10:45AM (#36021439)
Yes. The Halting Problem is just Gõdel incompleteness in drag. They're both the same idea and they're both thoroughly proven.
Re:The Absurdity Of Stacks by explaininjs on Sunday May 21, 2023 @12:51PM (#36022696)
I had originally written something to that effect, but recanted after I saw Turing claimed “what I shall prove is quite different from the well-known results of Gödel”. I’d need to sit down longer to determine how equivalent they really are.
Re:The Absurdity Of Stacks by dreamcompiler on Sunday May 21, 2023 @01:09PM (#36022874)
Would love to see the reference for this. I expect he might be referring to the idea of executing an embodied algorithm on a machine, while Gödel was talking about pure math.
Re:The Absurdity Of Stacks by explaininjs on Sunday May 21, 2023 @01:51PM (#36023227)
Re:The Absurdity Of Stacks by tsimionescu on Sunday May 21, 2023 @08:59AM (#36020456)
The halting problem (writing an algorithm which can take any other algorithm and an initial condition and return true/false for whether it halts or not) has nothing to do with P or NP. Even if all algorithms were solvable in O(n), the halting problem would still be unsolvable.