Geometric and Harmonic Analysis on Homogeneous Spaces
Geometric and Harmonic Analysis on Homogeneous Spaces
复制标题
齐次空间的几何和调和分析
DOI:
--
复制
发表时间:
2013
期刊:
影响因子:
--
通讯作者:
L. Accardi
中科院分区:
文献类型:
--
作者:
L. Abdelmoula;I. Kédim;L. Accardi
Lobna Abdelmoula : The Selberg-Weil-Kobayashi local rigidity Theorem for exponential Lie groups. A local rigidity Theorem proved by A. Selberg and A. Weil for Riemannian symmetric spaces and generalized by T. Kobayashi for a non-Riemannian homogeneous space G/H, asserts that there are no continuous deformations of a cocompact discontinuous subgroup Γ for G/H in the setting of a linear non-compact semi-simple Lie group G except some few cases : G is not locally isomorphic to SL2(R) for H compact or G is not locally isomorphic to SO(n, 1) or SU(n, 1) for G × G and H = ∆G. When in large contrast G is assumed to be exponential solvable and H ⊂ G a maximal subgroup, we prove an analogue of such a Theorem stating that the local rigidity holds on the parameter space R(Γ, G,H) if and only if G is isomorphic to the two-dimensional group of a ne transformations of the line ax+ b. Remarkably, we do also drop the assumption on Γ to be uniform for G/H. This is a joint work with Ali Baklouti and Imed Kedim. Luigi Accardi : In nite dimensional Lie algebras and renormalized higher powers of white noise. The problem of de ning, in an operational way, renormalized powers of free quantum elds (white noises in mathematical language) has been a central one in mathematical physics for the past 50 years (see the paper [3] for a survey). In 1999 a new, Lie algebraic, approach to this problem was proposed by Accardi, Lu and Volovich and has led, through the contributions of a multiplicity of authors, to the construction of the renormalized square of (quantum) white noise (RSWN) and to its identi cation with the theory of unitary representations of the current algebra over R of sl(2,R). The success and the non-triviality of the theory in the quadratic case naturally rose the problem of extending these results to powers higher than 2. This program has been systematically pursued by Accardi and Boukas in the past 14 years and has led to the conclusion that the role of sl(2,R), for higher powers is an in nite dimensional Lie algebra 'strictly related' the Virasoro Zamolodzhikov hierarchy of Lie algebras, introduced in the theory of strings for totally di erent purposes (the relation