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Volume 30, Number 2 (2009) A BSTR A ABSTRACTS CTS mailing offices 2000 MATHEMATICS and additional of Papers Presented to the Periodicals postage SUBJECT paid at Providence, RI American Mathematical Society CLASSIFICATION Volume 30, Number 2, Issue 156 Spring 2009 Compiled in the Editorial Offices of MATHEMATICAL REVIEWS and ZENTRALBLATT MATH 00 General 44 Integral transforms, operational calculus 01 History and biography 45 Integral equations 03 Mathematical logic and foundations 46 Functional analysis Editorial Committee 05 Combinatorics 47 Operator theory 06 Order, lattices, ordered 49 Calculus of variations and optimal Robert J. Daverman, Chair Volume 30 • Number 2 Spring 2009 Volume algebraic structures control; optimization Susan J. Friedlander 08 General algebraic systems 51 Geometry 11 Number theory 52 Convex and discrete geometry Michel L. Lapidus 12 Field theory and polynomials 53 Differential geometry Matthew Miller 13 Commutative rings and algebras 54 General topology 14 Algebraic geometry 55 Algebraic topology Steven H. Weintraub 15 Linear and multilinear algebra; 57 Manifolds and cell complexes matrix theory 58 Global analysis, analysis on manifolds 16 Associative rings and algebras 60 Probability theory and stochastic 17 Nonassociative rings and algebras processes 18 Category theory; homological 62 Statistics Abstracts for algebra 65 Numerical analysis 19 K-theory 68 Computer science Urbana, March 27–29, 2009 ........................ 389 20 Group theory and generalizations 70 Mechanics of particles and systems 22 Topological groups, Lie groups 74 Mechanics of deformable solids Raleigh, April 4–5, 2009 .............................. 469 26 Real functions 76 Fluid mechanics 28 Measure and integration 78 Optics, electromagnetic theory 30 Functions of a complex variable 80 Classical thermodynamics, heat transfer 31 Potential theory 81 Quantum theory 32 Several complex variables and 82 Statistical mechanics, structure of matter analytic spaces 83 Relativity and gravitational theory 33 Special functions 85 Astronomy and astrophysics 34 Ordinary differential equations 86 Geophysics 35 Partial differential equations 90 Operations research, mathematical 37 Dynamical systems and ergodic programming theory 91 Game theory, economics, social and 39 Difference and functional equations behavioral sciences 40 Sequences, series, summability 92 Biology and other natural sciences 41 Approximations and expansions 93 Systems theory; control 42 Fourier analysis 94 Information and communication, circuits 43 Abstract harmonic analysis 97 Mathematics education ISSN 0192-5857 Pages 389–542 AMS Abstracts of Papers Presented to the AMS Abstracts of Papers Presented ISSN 0192-5857 American Mathematical Society 201 Charles Street, Providence, RI 02904-2294 USA GST No. R121892046 AMS License or copyright restrictions may apply to redistribution; see https://www.ams.org/journal-terms-of-use 160 Pages on 40 lb paper • Spine: 1/4" • Print in Black Ink • Trim 7" x 10" SUBMISSION INFORMATION ABSTRACTS PUBLISHED IN THIS JOURNAL are those submitted by authors who intend to present them at AMS meetings (see the front cover). The abstracts for each meeting are sorted by the two-digit 2000 Mathematics Subject Classification chosen by the author and appear in the order received. See the back cover for the 2000 Mathematics Subject Classification. THE SUITABILITY OF A PAPER for presentation to the Society is judged from the abstract as outlined in Article X, Section 6 of the bylaws: Papers intended for presentation at any meeting of the Society shall be passed upon in advance by a program committee appointed by or under the authority of the Council; and only such papers shall be presented as shall have been approved by such committee. Papers in form unsuitable for publication, if accepted for presentation, shall be referred to on the program as preliminary communications or reports. In addition, the editors of the Abstracts have adopted the following policy: In order to be accepted for publication, an abstract must have mathematical research content. It should not contain libelous, defamatory, or tasteless remarks, commercial promotions, nor political or religious arguments. Papers may not be presented if published in full before the date of the Society meeting or if previously presented to any learned Society except the National Academy of Sciences or the Royal Society of Canada. The AMS assumes no responsibility for the content or inappropriate remarks in any published abstract. GENERAL INFORMATION ON ABSTRACTS is found at http://www.ams.org/abstracts. ABSTRACTS ARE PRINTED from copy submitted by the author. Web submission is the required electronic format. To view the interactive template, visit the Abstracts submission page on the AMS website at http://www.ams.org/ cgi-bin/abstracts/abstract.pl. Step-by-step submission instructions are included in the template. No knowl- edge of LATEX is necessary; however, any mathematical displays or accent marks in text or in names must be coded in LATEX. 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Box 845904, Boston, MA 02284-5904 USA; all correspondence relating to advance registration for meetings should be addressed to the Society, 201 Charles Street, Providence, RI 02904-2294 USA. Abstracts of Papers Presented to the American Mathematical Society (ISSN 0192-5857) is published four times a year by the American Mathematical Society at 201 Charles Street, Providence, RI 02904-2294. The subscription price for Volume 30 (2009) is US$144 list, US$115 institutional member, US$86 individual member. A late charge of 10% of the subscription price will be imposed on orders received from nonmembers after January 1 of the subscription year. Periodicals postage paid at Providence, RI. Add for postage: Surface delivery to destinations outside the U.S.—US$10, to India—US$16. Expedited delivery to destinations in North America—US$14, elsewhere—US$40. POSTMASTER: Send address change notices to Abstracts of Papers Presented to the American Mathematical Society, 201 Charles Street, Providence, RI 02904-2294 USA. c 2009 by the American Mathematical Society. All rights reserved. Printed in the United States of America. ∞ This journal is printed on acid-free paper and falls within the guidelines established to ensure permanence and durability. License or copyright restrictions may apply to redistribution; see https://www.ams.org/journal-terms-of-use 10987654321 1312111009 PAPERS PRESENTED AT MEETINGS THIS CALENDAR lists meetings of the Society which have been approved by the Council at which papers may be presented. Programs of Annual Meetings appear in the Notices and on the AMS website; programs for sectional meetings appear on the AMS Web pages in the Meetings & Conferences section, and are electronically archived in the Notices section on the AMS website. ABSTRACT ABSTRACT MEETING # DATE PLACE DEADLINE ISSUE 1049 April 25–26, 2009 San Francisco, CA March 3 Vol 30, No. 3 1050 April 25–26, 2009 Worcester, MA March 3 Vol 30, No. 3 1051 October 16–18, 2009 Waco, TX August 25 Vol 30, No. 4 1052 October 24–25, 2009 University Park, PA September 1 Vol 30, No. 4 1053 October 30–November 1, Boca Raton, FL September 8 Vol 30, No. 4 2009 1054 November 7–8, 2009 Riverside, CA September 15 Vol 30, No. 4 1055 December 16–20, 2009 Seoul, South Korea TBA TBA 1056 January 13–16, 2010 San Francisco, CA September 22 Vol 31, No. 1 URBANA, IL, March 27–29, 2009 Abstracts of the 1047th Meeting. 00 General 1047-00-2 Gilles Pisier*, Texas A & M University amd Universit´eParisVI.Complex interpolation between Hilbert, Banach and operator spaces. Let B(X, Y ) denote the Banach space of bounded operators between two Banach spaces X, Y . We describe the complex interpolation spaces θ θ (B(p0 ),B(p1 )) or (B(Lp0 ),B(Lp1 )) for any pair 1 ≤ p0,p1 ≤∞and 0 <θ<1. In the same vein, given a locally compact Abelian group G,let M(G) (resp. PM(G)) be the space of complex measures (resp. pseudo-measures) on G equipped with the usual | | norm µ M(G) = µ (G) (resp. ˛ ˛ b µPM(G) =sup{|µˆ(γ)| γ ∈ G}). We describe similarly the interpolation space (M(G),PM(G))θ. Various extensions and variants of this result will be given, e.g. to Schur multipliers on B(2) and to operator spaces. Motivated by a question of Vincent Lafforgue, we study the Banach spaces X satisfying the following property: there is a function ε → ∆X (ε) tending to zero with ε>0 such that every operator T : L2 → L2 with T ≤ε that is simultaneously contractive (i.e. of α norm ≤ 1) on L1 and on L∞ must be of norm ≤ ∆X (ε)onL2(X). We show that ∆X (ε) ∈ O(ε )forsomeα>0 iff X is isomorphic to a quotient of a subspace of an ultraproduct of θ-Hilbertian spaces for some θ>0where θ-Hilbertian is meant in a slightly more general sense than in our previous work. (Received May 27, 2008) 1047-00-19 Stewart E Brekke* ([email protected]), 2900 Maple Ave, Downers Grove, IL 60515. Geometric Figures as Sets of Convergent, Divergent and Parallel Lines and Surfaces. Preliminary report. Plane figures such as angles, triangles and polygons, to name a few,can be thought of as sets of convergent, divergent and parallel lines.
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