June 2014 - Banach - mathdept.okstate.edu

Abstract of a paper by Eusebio Gardella and Hannes Thiel
by alspach＠math.okstate.edu 16 Jun '14

16 Jun '14

This is an announcement for the paper "Banach algebras generated by an invertible isometry of an $L^p$-space" by Eusebio Gardella and Hannes Thiel. Abstract: We study and classify Banach algebras that are generated by an invertible isometry of an $L^p$-space together with its inverse. We associate to each such isometry a spectral invariant which contains considerably more information than its spectrum as an operator. We show that this invariant describes the isometric isomorphism type of the Banach algebra that the isometry generates together with its inverse. In the case of invertible isometries with full spectrum, these Banach algebras parametrize all completions of the group algebra $\mathbb{C}[\mathbb{Z}]$ corresponding to unital, contractive representations on $L^p$-spaces. The extreme cases are the algebra of $p$-pseudofunctions on $\mathbb{Z}$, and the commutative $C^*$-algebra $C(S^1)$. Moreover, there are uncountably many non-isometrically isomorphic "intermediate" algebras, all of which are shown to be closed under continuous functional calculus. Archive classification: math.FA math.OA Mathematics Subject Classification: Primary: 46J40, 46H35. Secondary: 47L10 Remarks: 43 pages Submitted from: gardella(a)uoregon.edu The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/1405.5589 or http://arXiv.org/abs/1405.5589

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Abstract of a paper by S Dutta and D Khurana
by alspach＠math.okstate.edu 16 Jun '14

16 Jun '14

This is an announcement for the paper "Ordinal indices for complemented subspaces of l_p" by S Dutta and D Khurana. Abstract: We provide complete isomorphic invariance of a class of translation invariant complemented subspaces of L_p constructed by Bourgain, Rosenthal and Schechtman. We compute ordinal L_p-indices for this class. We further show that the isometric index of a tree subspace over a well founded tree is an invariance for the order of the tree. Finally we provide a dichotomy for the subspaces of L_p with small ordinal indices. Archive classification: math.FA Submitted from: divyakhurana11(a)gmail.com The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/1405.4499 or http://arXiv.org/abs/1405.4499

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Abstract of a paper by T. Kappeler, A. Savchuk, A. Shkalikov, and P. Topalov
by alspach＠math.okstate.edu 16 Jun '14

16 Jun '14

This is an announcement for the paper "Interpolation of nonlinear maps" by T. Kappeler, A. Savchuk, A. Shkalikov, and P. Topalov. Abstract: Let $(X_0, X_1)$ and $(Y_0, Y_1)$ be complex Banach couples and assume that $X_1\subseteq X_0$ with norms satisfying $\|x\|_{X_0} \le c\|x\|_{X_1}$ for some $c > 0$. For any $0<\theta <1$, denote by $X_\theta = [X_0, X_1]_\theta$ and $Y_\theta = [Y_0, Y_1]_\theta$ the complex interpolation spaces and by $B(r, X_\theta)$, $0 \le \theta \le 1,$ the open ball of radius $r>0$ in $X_\theta$, centered at zero. Then for any analytic map $\Phi: B(r, X_0) \to Y_0+ Y_1$ such that $\Phi: B(r, X_0)\to Y_0$ and $\Phi: B(c^{-1}r, X_1)\to Y_1$ are continuous and bounded by constants $M_0$ and $M_1$, respectively, the restriction of $\Phi$ to $B(c^{-\theta}r, X_\theta)$, $0 < \theta < 1,$ is shown to be a map with values in $Y_\theta$ which is analytic and bounded by $M_0^{1-\theta} M_1^\theta$. Archive classification: math.FA Submitted from: p.topalov(a)neu.edu The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/1405.4253 or http://arXiv.org/abs/1405.4253

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Abstract of a paper by A. Jimenez-Vargas
by alspach＠math.okstate.edu 16 Jun '14

16 Jun '14

This is an announcement for the paper "Weakly compact composition operators on spaces of Lipschitz functions" by A. Jimenez-Vargas. Abstract: Let $X$ be a pointed compact metric space. Assuming that $\mathrm{lip}_0(X)$ has the uniform separation property, we prove that every weakly compact composition operator on spaces of Lipschitz functions $\mathrm{Lip}_0(X)$ and $\mathrm{lip}_0(X)$ is compact. Archive classification: math.FA Mathematics Subject Classification: 47B33, 47B07, 26A16 Remarks: 6 pages Submitted from: ajimenez(a)ual.es The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/1405.4267 or http://arXiv.org/abs/1405.4267

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Informal Analysis and Probability Seminar, October 17-19, 2014
by zvavitch＠math.kent.edu 11 Jun '14

11 Jun '14

Dear Colleague, Analysis/Probability group at the University of Michigan, and the Analysis group at Kent State University are happy to announce a meeting of the Informal Analysis and Probability Seminar, which will run at the Department of Mathematics at University of Michigan October 17-19, 2014. The plenary lecture series will be given by: Olivier Guedon (Pairs-Est University and University of Michigan), and Fedor Nazarov (Kent State) Each speaker will deliver a four hour lecture series designed to be accessible for graduate students. Funding is available to cover the local expenses, and possibly travel expenses, of a limited number of participants. Graduate students, postdoctoral researchers, and members of underrepresented groups are particularly encouraged to apply for support. Further information, and an online registration form, can be found online http://dept.math.lsa.umich.edu/conferences/informalAnalysis/. We encourage you to register as soon as possible, but to receive a support and/or help with hotel reservation, please, do register before September 5, 2014. Please feel free to contact us at rudelson(a)umich.edu / romanv(a)umich.edu for any further information. Sincerely, Analysis/Probability group at the University of Michigan, and the Analysis group at Kent State University

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Fall School ''Metric Embeddings: Constructions and Obstructions''
by BAUDIER Florent 02 Jun '14

02 Jun '14

Dear Colleagues, We are looking for PhD students, postdocs or very young researchers that might be interested in being an active participant of the Fall School ''Metric Embeddings: Constructions and Obstructions'', that we will be organizing in Paris, 3-7 November 2014. The scientific committee will select 12 active participants from the pool of applicants. The deadline to apply is June 30, 2014. The description of the school, its organization and the application and selection processes are fully explained on the website of the Fall School. http://www.math.tamu.edu/~florent/fallschool.html The accommodation in Paris of an active participant will be fully taken care off and we should be able to partially (and eventually fully) cover its travel expenses. Feel free to spread the word to whom you think might be interested. Feel free also, to email us for additional information at florent.baudier(a)imj-prg.fr The organizing committee, F. Baudier (Institut de Mathematiques de Jussieu-Paris Rive Gauche and Texas A&M University) G. Godefroy (Institut de Mathematiques de Jussieu-Paris Rive Gauche, CNRS) P. Pansu (Universite Paris-Sud 11) R. Tessera (Universite Paris-Sud 11, CNRS)

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