Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The multicomponent 2D Toda hierarchy: Discrete flows and string
  equations   The multicomponent 2D Toda hierarchy is analyzed through a factorization
problem associated to an infinite-dimensional group. A new set of discrete
flows is considered and the corresponding Lax and Zakharov--Shabat equations
are characterized. Reductions of block Toeplitz and Hankel bi-infinite matrix
types are proposed and studied. Orlov--Schulman operators, string equations and
additional symmetries (discrete and continuous) are considered. The
continuous-discrete Lax equations are shown to be equivalent to a factorization
problem as well as to a set of string equations. A congruence method to derive
site independent equations is presented and used to derive equations in the
discrete multicomponent KP sector (and also for its modification) of the theory
as well as dispersive Whitham equations.

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The categories of this paper are: chem-ph
3
The categories of this paper are: physics
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The categories of this paper are: eess
13
The categories of this paper are: quant-ph
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The categories of this paper are: funct-an
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
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The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
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The categories of this paper are: supr-con
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The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an