Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Topological Strings, Flat Coordinates and Gravitational Descendants   We discuss physical spectra and correlation functions of topological minimal
models coupled to topological gravity. We first study the BRST formalism of
these theories and show that their BRST operator $Q=Q_s+Q_v$ can be brought to
$Q_s$ by a certain homotopy operator $U$, $UQU^{-1}=Q_s$ ($Q_s$ and $Q_v$ are
the $N=2$ and diffeomorphism BRST operators, respectively). The
reparametrization (anti)-ghost $b$ mixes with the supercharge operator $G$
under this transformation. Existence of this transformation enables us to use
matter fields to represent cohomology classes of the operator $Q$. We
explicitly construct gravitational descendants and show that they generate the
higher-order KdV flows. We also evaluate genus-zero correlation functions and
rederive basic recursion relations of two-dimensional topological gravity.

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The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: cs
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
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The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int