Direct integrals and spectral averaging
نویسندگان
چکیده
منابع مشابه
Spectral Averaging and the Krein Spectral Shift
We provide a new proof of a theorem of Birman and Solomyak that if A(s) = A0+ sB with B ≥ 0 trace class and dμs(·) = Tr(BEA(s)(·)B), then ∫ 1 0 [dμs(λ)] ds = ξ(λ)dλ where ξ is the Krein spectral shift from A(0) to A(1). Our main point is that this is a simple consequence of the formula: d ds Tr(f(A(s)) = Tr(Bf ′(A(s))). Let A and C = A+B be bounded self-adjoint operators and suppose that B ≥ 0 ...
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Spectral averaging techniques for one-dimensional discrete Schrödinger operators are revisited and extended. In particular, simultaneous averaging over several parameters is discussed. Special focus is put on proving lower bounds on the density of the averaged spectral measures. These Wegner type estimates are used to analyze stability properties for the spectral types of Jacobi matrices under ...
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ژورنال
عنوان ژورنال: Journal of Operator Theory
سال: 2013
ISSN: 0379-4024,1841-7744
DOI: 10.7900/jot.2010nov10.1918