Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Witt group of real surfaces   Let $V$ be an algebraic variety defined over $\mathbb R$, and $V_{top}$ the
space of its complex points. We compare the algebraic Witt group $W(V)$ of
symmetric bilinear forms on vector bundles over $V$, with the topological Witt
group $WR(V_{top})$ of symmetric forms on Real vector bundles over $V_{top}$ in
the sense of Atiyah, especially when $V$ is 2-dimensional. To do so, we develop
topological tools to calculate $WR(V_{top})$, and to measure the difference
between $W(V)$ and $WR(V_{top})$.

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The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
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The categories of this paper are: eess
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The categories of this paper are: plasm-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: q-fin