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arXiv · 2511.21384

Euler systems for $\mathrm{GSp}(4)$ over imaginary quadratic fields

Alexandros Groutides
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Abstract

We construct an Euler system attached to general-type cohomological cuspidal automorphic representations of $\mathrm{GSp}(4)$ twisted by a Groessencharacter of an imaginary quadratic field. We then use this to bound strict Selmer groups under standard hypotheses. In addition, our approach gives a way of extending the $\mathrm{GSp}(4)\times\mathrm{GL}(2)$ Euler system of Hsu-Jin-Sakamoto to a motivic statement which also covers certain small weights omitted in op$.$cit.

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Alexandros Groutides. 2025-11-26. Euler systems for $\mathrm{GSp}(4)$ over imaginary quadratic fields. https://arxiv.org/abs/2511.21384

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