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Amitsur Seminar: Shaul Zemel (HUJI) | Einstein Institute of Mathematics

Amitsur Seminar: Shaul Zemel (HUJI)

Date: 
Thu, 02/06/202211:00-12:00
Speaker: Shaul Zemel (HUJI)

Room: 209 Manchester building (Mathematics)

ZOOM linkhttps://huji.zoom.us/j/86579149134?pwd=QlhTTVF2K3Q4a0ZYK1ExMVVOb0JZdz09

Title: Generalized Hyperbolic Spaces Associated with Arbitrary Quadratic Forms

Abstract: The automorphism group of the real hyperbolic space in 2 and 3 dimensions are known to be PSL_2(R) and PSL_2(C) respectively, acting via fractional linear transformations. Vahlen found groups, now named after him, that are contained in appropriate Clifford groups and act in the same manner on the hyperbolic space of every dimension. While the Vahlen groups are general, the action on a hyperbolic-like space is based on an anisotropy condition. We show how to construct these objects from any quadratic form, over any field of characteristic not 2, including appropriate boundary components that are required in case the anisotropy condition fails.