arXiv math/05062762005-06-14math.DGmath-phmath.MP

Hilbert-Schmidt groups as infinite-dimensional Lie groups and their Riemannian geometry

Maria Gordina

英文摘要：

We describe the exponential map from an infinite-dimensional Lie algebra to an infinite-dimensional group of operators on a Hilbert space. Notions of differential geometry are introduced for these groups. In particular, the Ricci curvature, which is understood as the limit of the Ricci curvature of finite-dimensional groups, is calculated. We show that for some of these groups the Ricci curvature is $-\infty$.

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