Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chow's Theorem for Linear Spaces   If $\phi: L\to L'$ is a bijection from the set of lines of a linear space
$(P,L)$ onto the set of lines of a linear space $(P',L')$ ($\dim P, \dim P'\geq
3$), such that intersecting lines go over to intersecting lines in both
directions, then $\phi$ is arising from a collineation of $(P,L)$ onto
$(P',L')$ or a collineation of $(P,L)$ onto the dual linear space of $(P',L')$.
However, the second possibility can only occur when $(P,L)$ and $(P',L')$ are
3-dimensional generalized projective spaces.

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The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int
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The categories of this paper are: eess
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
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The categories of this paper are: ao-sci
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
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The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat