2005/03/18 by Yoram Last, Last, Yoram, Barry Simon +1
Mathematics · Physics and Astronomy · #35J10 #47A10 #47B36 #FOS: Mathematics #FOS: Physical sciences #Mathematical Physics (math-ph) #Spectral Theory (math.SP) #math-ph #math.MP #math.SP #msc:35J10 #msc:47A10 #msc:47B36
paper · pdf · doi:10.48550/arxiv.math/0503391
arxiv created 2005/07/19 · arxiv updated 2009/12/01
We provide a very general result that identifies the essential spectrum of broad classes of operators as exactly equal to the closure of the union of the spectra of suitable limits at infinity. Included is a new result on the essential spectra when potentials are asymptotic to isospectral tori. We also recover with a unified framework the HVZ theorem and Krein's results on orthogonal polynomials with finite essential spectra.