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arXiv · 2004.12490

Slopes in eigenvarieties for definite unitary groups

Lynnelle Ye
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Abstract

We generalize bounds of Liu-Wan-Xiao for slopes in eigencurves for definite unitary groups of rank $2$ to slopes in eigenvarieties for definite unitary groups of any rank. We show that for a definite unitary group of rank $n$, the Newton polygon of the characteristic power series of the $U_p$ Hecke operator has exact growth rate $x^{1+\frac2{n(n-1)}}$, times a constant proportional to the distance of the weight from the boundary of weight space. The proof goes through the classification of forms associated to principal series representations. We also give a consequence for the geometry of these eigenvarieties over the boundary of weight space.

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Lynnelle Ye. 2020-04-26. Slopes in eigenvarieties for definite unitary groups. https://arxiv.org/abs/2004.12490

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