Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Solving Bethe-Salpeter equation in Minkowski space   We develop a new method of solving Bethe-Salpeter (BS) equation in Minkowski
space. It is based on projecting the BS equation on the light-front (LF) plane
and on the Nakanishi integral representation of the BS amplitude. This method
is valid for any kernel given by the irreducible Feynman graphs. For massless
ladder exchange, our approach reproduces analytically the Wick-Cutkosky
equation. For massive ladder exchange, the numerical results coincide with the
ones obtained by Wick rotation.

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The categories of this paper are: q-bio
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: nlin
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The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
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The categories of this paper are: gr-qc
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
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The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org