Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Donaldson invariants of product ruled surfaces and two-dimensional gauge
  theories   Using the u-plane integral of Moore and Witten, we derive a simple expression
for the Donaldson invariants of $\Sigma_g \times S^2$, where $\Sigma_g$ is a
Riemann surface of genus g. This expression generalizes a theorem of Morgan and
Szabo for g=1 to any genus g. We give two applications of our results: (1) We
derive Thaddeus' formulae for the intersection pairings on the moduli space of
rank two stable bundles over a Riemann surface. (2) We derive the eigenvalue
spectrum of the Fukaya-Floer cohomology of $\Sigma_g \times S^1$.

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The categories of this paper are: alg-geom
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys