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29 votes
1 answer
3k views

The Riemann zeros and the heat equation

The Riemann xi function $\Xi(x)$ is defined, with $s=1/2+ix$, as $$ \Xi(x)=\frac12 s(s-1)\pi^{-s/2}\Gamma(s/2)\zeta(s)=2\int_0^\infty \Phi(u)\cos(ux) \, du, $$ where $\Phi(u)$ is defined as $$ 2\sum_{...
Stopple's user avatar
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60 votes
1 answer
6k views

What were the main ideas and gaps in Yoichi Miyaoka's attempted proof (1988) of Fermat's Last Theorem?

Out of sheer curiosity I have been reading Stewert and Tall's "Algebraic Number Theory and Fermat's Last Theorem" (2001). As it contains various bits of history, I found out to my own shame that I was ...
M.G.'s user avatar
  • 7,127
32 votes
2 answers
3k views

The Erdős–Turán conjecture or the Erdős conjecture?

This has been bothering me for a while, and I can't seem to find any definitive answer. The following conjecture is well known in additive combinatorics: Conjecture: If $A\subset \mathbb{N}$ and $$\...
Eric Naslund's user avatar
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8 votes
1 answer
595 views

Why was the factor $\frac12$ introduced in the Riemann $\xi$ function?

The factor $\frac12$ in the Riemann $\xi$ function: $$\xi(s)=\frac12 s(s-1)\,\pi^{-s/2}\,\Gamma(s/2)\,\zeta(s)$$ was introduced by Riemann, however appears to be redundant. Once he had arrived at: ...
Agno's user avatar
  • 4,169
6 votes
2 answers
713 views

Origin and variations of problem on $4xy-x-y$ being square

One of the forms in which the Diophantine equation in question can be found in the literature is this: Solve the equation \begin{eqnarray}z^{2} = 4xy-x-y \qquad \qquad (\ast)\end{eqnarray} in ...
José Hdz. Stgo.'s user avatar