Estimate of the norm ∥f(A1, A2)-f(B1, B2)∥ for pairs of self-adjoint commuting operators
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In this note we announce the estimate for the difference mentioned in the title, where are the lengths of intervals containing the spectra of the operators A1, B2 and A2, B2; the function f is from the class Lip 1 (with constant 1). The outline of the proof of this estimate is given.
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© Plenum Publishing Corporation 1985