Is There a Finite Number of Solutions to Fermat's Last Theorem?

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Discussion Overview

The discussion revolves around the implications of Fermat's Last Theorem, specifically addressing the claim that if there are solutions to the equation a^n+b^n=c^n, then there are only a finite number of them. Participants explore the validity of this claim and the assumptions underlying it.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant references a source claiming that if solutions exist for Fermat's equation, there are only a finite number for each n, citing Gerd Faltings' work.
  • Another participant suggests that the assumption gcd(a,b,c)=1 is likely necessary for the claim to hold.
  • A different participant asserts that there are zero solutions, implying a definitive stance on the existence of solutions.
  • One participant reflects on the historical significance of the theorem prior to its proof, suggesting it had importance in mathematical discussions.

Areas of Agreement / Disagreement

Participants express differing views on the existence of solutions to Fermat's Last Theorem, with some asserting there are none and others discussing the conditions under which finite solutions might exist. The discussion remains unresolved regarding the implications of the theorem and the assumptions involved.

Contextual Notes

The discussion touches on assumptions such as gcd(a,b,c)=1, which may not be explicitly stated in all contexts. There is also uncertainty regarding the implications of multiplying solutions by k^n for k larger than 1.

disregardthat
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I read in a book about Fermats last theorem that it has been proved that "if there are solutions to the equation a^n+b^n=c^n, then there are only a finite number of them". I searched this up and found this article:

http://findarticles.com/p/articles/mi_m1200/is_n12_v133/ai_6519267

A quote from the article states:

In 1983, Gerd Faltings, now at Princeton (N.J.) University, opened up a new direction in the search for a proof. As one consequence of his proof of the Mordell conjecture (SN: 7/23/83, p.58), he showed that if there are any solutions to Fermat's equations, then there are only a finite number of them for each value of n.

How can this be?
Suppose a_0, b_0 and c_0 are solutions to the equation a^n+b^n=c^n for a specified n, i.e a_0^n+b_0^n=c_0^n. But by multiplying by k^n where k is a natural number larger than 1 yields (a_0k)^n+(b_0k)^n=(c_0k)^n which is a different solution. This is true for all values of k larger than 1, so I cannot see how the theorem is true.

Please clarify!
 
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There's (probably) the unstated assumption that gcd(a,b,c)=1.
 
Yes, I thought of that, but I didn't see it anywhere. It is most likely true though.
 
There are 0 solutions, so it is definitely (not most likely) true!
 
Of course =), but before fermats was proven this theorem was probably of importance.
 

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