Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Field reduction and linear sets in finite geometry   Based on the simple and well understood concept of subfields in a finite
field, the technique called `field reduction' has proved to be a very useful
and powerful tool in finite geometry. In this paper we elaborate on this
technique. Field reduction for projective and polar spaces is formalized and
the links with Desarguesian spreads and linear sets are explained in detail.
Recent results and some fundamental ques- tions about linear sets and scattered
spaces are studied. The relevance of field reduction is illustrated by
discussing applications to blocking sets and semifields.

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The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
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The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
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The categories of this paper are: econ
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn