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The essential spectrum of holomorphic Toeplitz operators on H p spaces

Mats Andersson, Sebastian Sandberg (2003)

Studia Mathematica

We compute the essential Taylor spectrum of a tuple of analytic Toeplitz operators T g on H p ( D ) , where D is a strictly pseudoconvex domain. We also provide specific formulas for the index of T g provided that g - 1 ( 0 ) is a compact subset of D.

The generalized Toeplitz operators on the Fock space F α 2

Chunxu Xu, Tao Yu (2024)

Czechoslovak Mathematical Journal

Let μ be a positive Borel measure on the complex plane n and let j = ( j 1 , , j n ) with j i . We study the generalized Toeplitz operators T μ ( j ) on the Fock space F α 2 . We prove that T μ ( j ) is bounded (or compact) on F α 2 if and only if μ is a Fock-Carleson measure (or vanishing Fock-Carleson measure). Furthermore, we give a necessary and sufficient condition for T μ ( j ) to be in the Schatten p -class for 1 p < .

The Quantum Birkhoff Normal Form and Spectral Asymptotics

San Vũ Ngọc (2006)

Journées Équations aux dérivées partielles

In this talk we explain a simple treatment of the quantum Birkhoff normal form for semiclassical pseudo-differential operators with smooth coefficients. The normal form is applied to describe the discrete spectrum in a generalised non-degenerate potential well, yielding uniform estimates in the energy E . This permits a detailed study of the spectrum in various asymptotic regions of the parameters ( E , ) , and gives improvements and new proofs for many of the results in the field. In the completely resonant...

The quasi-canonical solution operator to ¯ restricted to the Fock-space

Georg Schneider (2005)

Czechoslovak Mathematical Journal

We consider the solution operator S μ , ( p , q ) L 2 ( μ ) ( p , q ) to the ¯ -operator restricted to forms with coefficients in μ = f f is entire and n | f ( z ) | 2 d μ ( z ) < . Here μ , ( p , q ) denotes ( p , q ) -forms with coefficients in μ , L 2 ( μ ) is the corresponding L 2 -space and μ is a suitable rotation-invariant absolutely continuous finite measure. We will develop a general solution formula S to ¯ . This solution operator will have the property S v ( p , q ) v ( p , q + 1 ) . As an application of the solution formula we will be able to characterize compactness of the solution operator in terms of compactness of commutators...

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