Mathematicians / folks knowledgeable on the subject - do you think Fermat had an error in his (lost) proof? Or that there exists a solution that perhaps is more straightforward than Wiles's?
My understanding is that Wiles had to use a ton of math (and invent some new math?) that had not yet been invented in Fermat's time.
He wrote his note in his copy of Arithmetica around 1637.
He most likely wrote his proof for the case of n=4 in the 1640s.
He sent letters to other mathematicians in 1640, 1657 where he talks about the case of n=3 but writes in such a way that it seems like he does not have the answer.
Why would he write n=4 after? If he had a generalized proof?
Why would he tease other mathematicians with a special case in 1657 if he already had a generalized proof?
My personal guess is he figured out later that his proof was broken or limited and never got around to fixing it.
I think you have an odd definition of "responsible". Many (most?) theorems start out as conjectures, and I would strongly disagree that just because someone first formulated a problem that they're "responsible" for the eventual solution.
That's not true. Even early on, most mathematicians doubted he had a proof. But I'd check out the history of the problem as described on Wikipedia. There was considerable research into the problem before Fermat, and general research into Diophantine equations had gone on for over a thousand years before Fermat. I have no doubt there would have been significant interest into solving the problem even if Fermat had never written his "I have a proof but it's too big to fit in the margin" note.
But yes had him not pointed it out maybe it would have been relegated to a mathematical curiosity or something
I think there's a deeper (but simpler) reason for it, besides the way Wiles proved it
For one thing, Fermat wasn’t actually a “professional” mathematician. He was a lawyer and judge and was known for having remarkable intuition but not really troubling himself too much with details of proofs etc. For example Descartes famously called him a “deficient mathematician”[1] in an angry exchange of letters over a technique that Fermat had discovered to geometrically construct a tangent to a particularly problematic curve called Descartes’ Folia using a technique we would now recognise as being the definition of the derivative as the limit of the difference quotient.
[1] Explained entertainingly here https://youtu.be/xKfEmbWBgvM?is=qLnPvPXGDqgJCDC3
Descartes was himself a lawyer (by training) then there were Leibnitz, Cayley, Viete. If you include Physics you will get a bigger list.
Descartes and Fermat ran a mutual admiration society, don't read to much into it.
Both had independently come up with coordinate geometry, linking algebra and geometry
I agree Fermat probably had a wrong proof but curb your condescension towards lawyers making contributions in mathematics.
Yes, with million-to-one odds. Though I'd say "error or equivalent shortcoming, for the general case".
> that perhaps is more straightforward than Wiles's?
I don't recall a mathematical definition of "straightforward", but yes. Ignoring minor improvements, I'd guess there's a much better proof...though that might require a century of new developments in related parts of mathematics, before we'll have the necessary tools to write it down.