The Affine Grassmannian
نویسنده
چکیده
The affine Grassmannian is an important object that comes up when one studies moduli spaces of the form BunG(X), where X is an algebraic curve and G is an algebraic group. There is a sense in which it describes the local geometry of such moduli spaces. I’ll describe the affine Grassmannian as a moduli space, and construct it concretely for some concrete groups. References, including the construction of perverse sheaves on affine Grassmannians, include the papers [4], [1], the book [5] and set of seminar notes [3] by Gaitsgory.
منابع مشابه
Pursuing the Double Affine Grassmannian Ii: Convolution
This is the second paper of a series (started by [3]) which describes a conjectural analog of the affine Grassmannian for affine Kac-Moody groups (also known as the double affine Grassmannian). The current paper is dedicated to describing a conjectural analog of the convolution diagram for the double affine Grassmannian. In the case when G = SL(n) our conjectures can be derived from [12].
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تاریخ انتشار 2013