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arXiv · 2207.12145

The slope-invariant of local ghost series under direct sum

Rufei Ren
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Abstract

The ghost conjecture is first provided by Bergdall and Pollack in [BP-1,BP-2] to study the Up-slopes of spaces of modular forms, which, so far, has already brought plenty of important results. The local version of this conjecture under genericity condition has been solved by Liu-Truong-Xiao-Zhao in [LTXZ-1, LTXZ-2]. In the current paper, we prove a necessary and sufficient condition for a sequence of local ghost series to satisfy that their product has the same Newton polygon to the ghost series build from the direct sum of their associated modules. That answers a common question asked in both [BP2,LTXZ-1].

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Rufei Ren. 2022-07-25. The slope-invariant of local ghost series under direct sum. https://arxiv.org/abs/2207.12145

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