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arXiv · 1805.00392

Derived Hecke algebra and automorphic L-invariants

Lennart Gehrmann
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Abstract

Let $π$ be a cohomological automorphic representation of $PGL(2)$ over a number field of arbitrary signature and assume that the local component of $π$ at a prime $\mathfrak{p}$ is the Steinberg representation. In this situation one can define an automorphic $\mathcal{L}$-invariant for each cohomological degree in which the system of Hecke eigenvalues associated to $π$ occurs. We show that these $\mathcal{L}$-invariants are (essentially) the same if the $π$-isotypic component of the cohomology is generated by the minimal degree cohomology as a module over Venkatesh's derived Hecke algebra.

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Lennart Gehrmann. 2019-07-17. Derived Hecke algebra and automorphic L-invariants. https://doi.org/10.1090/tran%2F7815

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