Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Well-defined quasiparticles in interacting metallic grains   We analyze spectral functions of mesoscopic systems with large dimensionless
conductance, which can be described by a universal Hamiltonian. We show that an
important class of spectral functions are dominated by one single state only,
which implies the existence of well-defined (i.e. infinite-lifetime)
quasiparticles. Furthermore, the dominance of a single state enables us to
calculate zero-temperature spectral functions with high accuracy using the
density-matrix renormalization group. We illustrate the use of this method by
calculating the tunneling density of states of metallic grains and the magnetic
response of mesoscopic rings.

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The categories of this paper are: stat
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
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The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: physics
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The categories of this paper are: acc-phys