Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A renormalised hamiltonian approach for a resonant valence bond
  wavefunction   The effective Hamiltonian of strongly correlated electrons on a square
lattice is replaced by a renormalised Hamiltonian and the factors that
renormalise the kinetic energy of holes and the Heisenberg spin-spin coupling
are calculated using a Gutzwiller approximation scheme. The accuracy of this
renormalisation procedure is tested numerically and found to be qualitatively
excellent. Within the scheme a resonant valence bond (RVB) wavefunction is
found at half-filling to be lower in energy than the antiferromagnetic state.
If the wavefunction is expressed in fermion operators, local SU(2) and U(l)
invariance leads to a redundancy in the representation. The introduction of
holes removes these local invariances and we find that a d-wave RVB state is
lowest in energy. This state has a superconducting order parameter whose
amplitude is linear in the density of holes.

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The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
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The categories of this paper are: patt-sol
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
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The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: q-fin
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: econ