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arXiv · 0904.1559

Conical Distributions on the Space of Flat Horocycles

Fulton B. Gonzalez
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Abstract

Let $G_0=K\ltimes\mathfrak p$ be the Cartan motion group associated with a noncompact semisimple Riemannian symmetric pair $(G, K)$. Let $\frak a$ be a maximal abelian subspace of $\mathfrak p$ and let $\p=\a+\q$ be the corresponding orthogonal decomposition. A flat horocycle in $\p$ is a $G_0$-translate of $\q$. A conical distribution on the space $Ξ_0$ of flat horocycles is an eigendistribution of the algebra $\mathbb D(Ξ_0)$ of $G_0$-invariant differential operators on $Ξ_0$ which is invariant under the left action of the isotropy subgroup of $G_0$ fixing $\q$. We prove that the space of conical distributions belonging to each generic eigenspace of $\mathbb D(Ξ_0)$ is one-dimensional, and we classify the set of all conical distributions on $Ξ_0$ when $G/K$ has rank one.

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Fulton B. Gonzalez. 2009-04-09. Conical Distributions on the Space of Flat Horocycles. https://arxiv.org/abs/0904.1559

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