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Hittade 2 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Continuity and Positivity Problems in Pseudo-differential Calculus

   Författare :Joachim Toft; Matematik (naturvetenskapliga fakulteten); []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; funktionsanalys; fourieranalys; Serier; functional analysis; Fourier analysis; Series; Entropy.; Young s inequality; Twisted convolution; Schatten-von Neumann; Lower bounds; Weyl Calculus; Pseudo-differential Operqator; Continuity; Positivity;

   Sammanfattning : The paper deals with various positivity and continuity questions arising in the Weyl calculus of pseudo-differential operators. Let W be a symplectic vector space. LÄS MER

3. 2. Reordering in Noncommutative Algebras, Orthogonal Polynomials and Operators

   Författare :John Musonda; Sergei Silvestrov; Sten Kaijser; Johan Richter; Viktor Abramov; Mälardalens högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mathematics Applied Mathematics; matematik tillämpad matematik;

   Sammanfattning : The main object studied in this thesis is the multi-parametric family of unital associative complex algebras generated by the element $Q$ and the finite or infinite set $\{S_j\}_{j\in J}$ of elements satisfying the commutation relations $S_jQ=\sigma_j(Q)S_j$, where $\sigma_j$ is a polynomial for all $j\in J$. A concrete representation is given by the operators $Q_x(f)(x)=xf(x)$ and $\alpha_{\sigma_j}(f)(x)=f(\sigma_j(x))$ acting on polynomials or other suitable functions. LÄS MER