
A variety $ X $ is $ F $-split if there exists an $ \mathcal{O}_{X} $-linear map $ \phi: F_{\ast}(\mathcal{O}_{X}) \to \mathcal{O}_{X} $ such that $ \phi \circ F^{\sharp} = \operatorname{id}_{\mathcal{O}_{X}} $. Such a map $ \phi $ is called a splitting. A closed sub-scheme $ Y $ of $ X $ is co...

Two additional papers in combinatorics (That I managed to find on line) each having a beautiful and simple result.
On the Shannon Capacity of a Graph by Laszlo Lovasz
The Upper Bound Conjecture and Cohen Macaulay Rings by Richard Stanley

Convergence in the Fell topology is equivalent to convergence of matrix coefficients. In the finite-dimensional case, this is equivalent as $\rho_n(g) v \rightarrow \rho(g)v$.
Quote from Vogan (http://dedekind.mit.edu/~dav/iso3.pdf)
Suppose then that G is a real reductive Lie group. Write $\...

The Arithmetic fixed point theorem (see also MO/30874) states that if $F$ is a formula in number theory with only one free variable $v$, then there is a sentence $A$ such that number theory can prove $A \Leftrightarrow F_v(\underline{[A]})$. An immediate application is Gödel's Theorem.
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