Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An abstract elementary class non-axiomatizable in $L_{(\infty,\kappa)}$   We show that for any uncountable cardinal $\lambda$, the category of sets of
cardinality at least $\lambda$ and monomorphisms between them cannot appear as
the category of point of a topos, in particular is not the category of models
of a $L_{(\infty,\omega)}$-theory. More generally we show that for any regular
cardinal $\kappa < \lambda$ it is neither the category of $\kappa$-points of a
$\kappa$-topos, in particular, not the category of models of a
$L_{(\infty,\kappa)}$-theory. The proof relies on the construction of a
categorified version of the Scott topology, which constitute a left adjoint to
the functor sending any topos to its category of points and the computation of
this left adjoint evaluated on the category of sets of cardinality at least
$\lambda$ and monomorphisms between them. The same techniques also applies to a
few other categories. At least to the category of vector spaces of with bounded
below dimension and the category of algebraic closed fields of fixed
characteristic with bounded below transcendence degree.

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The categories of this paper are: eess
4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
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The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
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The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: plasm-ph
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The categories of this paper are: funct-an
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The categories of this paper are: econ
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The categories of this paper are: atom-ph