Estimate of the norm ∥f(A1, A2)-f(B1, B2)∥ for pairs of self-adjoint commuting operators
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