A Multi–Dimensional Lieb–Schultz–Mattis Theorem
نویسندگان
چکیده
For a large class of finite-range quantum spin models with half-integer spins, we prove that uniqueness of the ground state implies the existence of a low-lying excited state. For systems of linear size L, of arbitrary finite dimension, we obtain an upper bound on the excitation energy (i.e., the gap above the ground state) of the form (C logL)/L. This result can be regarded as a multi-dimensional Lieb-Schultz-Mattis theorem [7] and provides a rigorous proof of the main result in [4].
منابع مشابه
ar X iv : m at h - ph / 0 60 80 46 v 1 1 8 A ug 2 00 6 A MULTI - DIMENSIONAL LIEB - SCHULTZ - MATTIS THEOREM
For a large class of finite-range quantum spin models with half-integer spins, we prove that uniqueness of the ground state implies the existence of a low-lying excited state. For systems of linear size L, of arbitrary finite dimension, we obtain an upper bound on the excitation energy (i.e., the gap above the ground state) of the form (C log L)/L. This result can be regarded as a multi-dimensi...
متن کاملar X iv : m at h - ph / 0 60 80 46 v 2 2 7 D ec 2 00 7 A MULTI - DIMENSIONAL LIEB - SCHULTZ - MATTIS THEOREM
For a large class of finite-range quantum spin models with half-integer spins, we prove that uniqueness of the ground state implies the existence of a low-lying excited state. For systems of linear size L, with arbitrary finite dimension, we obtain an upper bound on the excitation energy (i.e., the gap above the ground state) of the form (C log L)/L. This result can be regarded as a multi-dimen...
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