Results 231 to 240 of about 32,952 (266)

Operator regularization and composite operators

Canadian Journal of Physics, 1990
We demonstrate how operator regularization can be used to compute radiative corrections to Green's functions involving composite operators. No divergences are encountered and no symmetry-breaking regulating parameter need be introduced into the initial Lagrangian.
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Essential Norms of Composition Operators

Integral Equations and Operator Theory, 2004
Recently, there has been considerable interest in studying lower and upper estimates for the essential norms of composition operators in function spaces. Sometimes, as a consequence, a necessary and sufficient condition for the composition operator to be compact on the function space can be obtained.
Gorkin, Pamela, MacCluer, Barbara D.
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UNIFORMLY BOUNDED COMPOSITION OPERATORS

Bulletin of the Australian Mathematical Society, 2015
We prove that if a uniformly bounded (or equidistantly uniformly bounded) Nemytskij operator maps the space of functions of bounded ${\it\varphi}$-variation with weight function in the sense of Riesz into another space of that type (with the same weight function) and its generator is continuous with respect to the second variable, then this generator ...
Głazowska, Dorota, Matkowski, Janusz
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Co-Rank of a Composition Operator

Canadian Mathematical Bulletin, 1986
AbstractA composition operator CT on L2(X, Σ,m) is a bounded linear transformation induced by a mapping T : X → X via CTf = f∘ T.If m has no atoms then the co-rank of CT (i.e., dim is either zero or infinite. As a corollary, when m has no atoms, CT is a Fredholm operator iff it is invertible.
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Implementations of program composition operations

1994
This paper reports on a number of implementations for a suite of composition operations of logic programs. We present and compare three implementations, which rely on different techniques: metaprogramming, program transformations, and extensions to the WAM, respectively.
Brogi A, Chiarelli A, Mancarella P, Mazzotta V, Pedreschi D, Renso C, Turini, F   +7 more
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The Norms of Compositions of Arithmetic Operators

Bulletin of the London Mathematical Society, 1987
Weighted inequalities which widely generalize the Turán-Kubilius inequality are established. The following is typical: Let w(m) be a non- negative real-valued arithmetic function which satisfies w(q) \(\ll 1\), w(qm) \(\ll w(q)w(m)\) uniformly for prime-powers q and positive integers m, \((q,m)=1\).
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Operational and compositional semantics of synchronous automaton compositions

2006
The state/transition paradigm has been used extensively for the description of event-driven, parallel systems. However, the lack for hierarchic structure in such descriptions usually prevents us from using this paradigm in a real programming language. We propose the Argos language for reactive systems. The basic components of a program are input/output-
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Analytic Toeplitz and Composition Operators

Canadian Journal of Mathematics, 1972
This paper is a continuation of [1] where we began the study of intertwining analytic Toeplitz operators. Recall that X intertwines two operators A and B if XA = BX. Let H2 be the Hilbert space of analytic functions in the open unit disk D for which
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Weighted composition operators on Fock spaces and their dynamics

Journal of Mathematical Analysis and Applications, 2021
Tom Carroll, Clifford Gilmore
exaly  

Operators commuting with self-adjoint weighted composition operators on H2

Complex Variables and Elliptic Equations, 2021
Eungil Ko
exaly