• Corpus ID: 235358526

Fermi isospectrality for discrete periodic Schrodinger operators

@inproceedings{Liu2021FermiIF,
  title={Fermi isospectrality for discrete periodic Schrodinger operators},
  author={Wencai Liu},
  year={2021}
}
. Let Γ = q 1 Z ⊕ q 2 Z ⊕· · ·⊕ q d Z , where q l ∈ Z + , l = 1 , 2 , · · · , d . Let ∆+ V be the discrete Schr¨odinger operator, where ∆ is the discrete Laplacian on Z d and the potential V : Z d → R is Γ-periodic. We prove three rigidity theorems for discrete periodic Schr¨odinger operators in any dimension d ≥ 3: In particular, all conclusions in (1), (2) and (3) hold if we replace the assumption “Fermi isospectrality” with a stronger assumption “Floquet isospectrality”. 

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Let H0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek}

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