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Sharp estimates for the Ornstein-Uhlenbeck operator

Giancarlo Mauceri, Stefano Meda, Peter Sjögren (2004)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

Let be the Ornstein-Uhlenbeck operator which is self-adjoint with respect to the Gauss measure γ on d . We prove a sharp estimate of the operator norm of the imaginary powers of on L p ( γ ) , 1 < p < ...

Sharp maximal functions associated with approximations of the identity in spaces of homogeneous type and applications

José María Martell (2004)

Studia Mathematica

In the context of the spaces of homogeneous type, given a family of operators that look like approximations of the identity, new sharp maximal functions are considered. We prove a good-λ inequality for Muckenhoupt weights, which leads to an analog of the Fefferman-Stein estimate for the classical sharp maximal function. As a consequence, we establish weighted norm estimates for certain singular integrals, defined on irregular domains, with Hörmander conditions replaced by some estimates which do...

Smooth operators in the commutant of a contraction

Pascale Vitse (2003)

Studia Mathematica

For a completely non-unitary contraction T, some necessary (and, in certain cases, sufficient) conditions are found for the range of the H calculus, H ( T ) , and the commutant, T’, to contain non-zero compact operators, and for the finite rank operators of T’ to be dense in the set of compact operators of T’. A sufficient condition is given for T’ to contain non-zero operators from the Schatten-von Neumann classes S p .

Spectral mapping framework

Anar Dosiev (2005)

Banach Center Publications

In this paper we suggest a general framework of the spectral mapping theorem in terms of parametrized Banach space bicomplexes.

Spectral mapping inclusions for the Phillips functional calculus in Banach spaces and algebras

Eva Fašangová, Pedro J. Miana (2005)

Studia Mathematica

We investigate the weak spectral mapping property (WSMP) μ ̂ ( σ ( A ) ) ¯ = σ ( μ ̂ ( A ) ) , where A is the generator of a ₀-semigroup in a Banach space X, μ is a measure, and μ̂(A) is defined by the Phillips functional calculus. We consider the special case when X is a Banach algebra and the operators e A t , t ≥ 0, are multipliers.

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