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Flow Equations and Normal Ordering

Elmar Koerding·Franz Wegner
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Abstract

In this paper we consider flow-equations where we allow a normal ordering which is adjusted to the one-particle energy of the Hamiltonian. We show that this flow converges nearly always to the stable phase. Starting out from the symmetric Hamiltonian and symmetry-broken normal ordering nearly always yields symmetry breaking below the critical temperature.

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Elmar Koerding, Franz Wegner. 2005-09-30. Flow Equations and Normal Ordering. https://doi.org/10.1088/0305-4470%2F39%2F6%2F001

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