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Response to Greiter's Comment

Eugene Demler·Shou-Cheng Zhang·Stefan Meixner·Werner Hanke
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Abstract

Greiter claimed erroneously that the pi-excitation of the Hubbard model has an energy of the order of U. This mistake originates from a inconsistent treatment of the two particle Hartree energy and the Hartee correction to the chemical potential. In any self-consistent calculations, these two contributions cancel exactly, as shown by Kohn, Luttinger and Ward. We also show that his interpretation of the finite-size studies is inconsistent.

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Eugene Demler, Shou-Cheng Zhang, Stefan Meixner, Werner Hanke. 1997-05-21. Response to Greiter's Comment. https://arxiv.org/abs/cond-mat/9705191

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