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arXiv · 1203.1494

Counting rule for Nambu-Goldstone modes in nonrelativistic systems

Yoshimasa Hidaka
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Abstract

The counting rule for Nambu-Goldstone modes is discussed using Mori's projection operator method in nonrelativistic systems at zero and finite temperatures. We show that the number of Nambu-Goldstone modes is equal to the number of broken charges, Q_a, minus half the rank of the expectation value of [Q_a,Q_b].

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Yoshimasa Hidaka. 2012-11-04. Counting rule for Nambu-Goldstone modes in nonrelativistic systems. https://doi.org/10.1103/physrevlett.110.091601

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