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arXiv · 2509.14881

Normalized Indexing for Ramification Subgroups

Stephen DeBacker·David Schwein·Cheng-Chiang Tsai
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Abstract

This expository note introduces a normalization of the indexing of the lower and upper numbering ramification subgroups of local class field theory. We then look at how this normalization interacts with base change for Langlands parameters.

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Stephen DeBacker, David Schwein, Cheng-Chiang Tsai. 2025-09-18. Normalized Indexing for Ramification Subgroups. https://arxiv.org/abs/2509.14881

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