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Care to tell us who did prove it then?

While the 1936 paper, "On Computable Numbers", doesn't explicitly mention the halting problem, it does cover the Entscheidungsproblem, and that the halting problem is undecidable follows trivially from that.



"Jack Copeland (2004) attributes the introduction of the term halting problem to the work of Martin Davis in the 1950s.[1]"

https://en.wikipedia.org/wiki/Halting_problem

Martin Davis did in the early 1950s after Turing's death.

> and that the halting problem is undecidable follows trivially from that.

Trivially? Took nearly 2 decades after Turing published his paper for Martin Davis to come up with the halting problem. And it required a reformulation of the Turing machine itself. Today, we view 'good' Turing machines as those that stop/halt. Turing viewed 'good' Turing machines as those that continued forever ( aka never stops ).


If you can solve the halting problem, then you can apply it to a solution checker that works by enumerating potential solutions and halting when it finds one. Therefore, if you've solved the halting problem then you've also solved the Entscheidungsproblem, and since the latter is impossible, it follows that the premise of having a solution to the halting problem is false.

Yes, that does seems trivial to me. Although maybe that just shows the brilliance of the people who came up with it and made it sound simple.

Did Turing's original machine not have a halting state? That does change things. You can hardly express the halting problem if you don't have the concept of halting.


Using your logic, Alonzo Church should be credited with the Turing machine and the halting problem since he solved Hilbert's Entscheidungsproblem before Turing did. If everything follows trivially from an answer to the same question, then Turing's solution follows trivially from Church.

Not sure why you are fixated on the Entscheidungsproblem. Turing's claim to fame isn't the entscheidungsproblem. If it were, nobody would know who Turing is because Church already solved the entscheidungsproblem. His contribution are the theoretical concept of Turing machines ( universal turing machines especially ) and computable numbers.

> Did Turing's original machine not have a halting state?

Are you asking me?

> You can hardly express the halting problem if you don't have the concept of halting.

He did have a concept of halting. He called them circular/unsatisfactory.

Did you even read his paper?


I did read the paper, 30 years ago.


I would recommend making those points on the article's talk page instead of (or in addition to) on here.


Why? I'm not a fan of wikipedia and don't wish to use my time to assist it in any way whatsoever. I've grown weary of wikipedia and much of tech/social media that profits off of free labor essentially.




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