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arXiv · 1609.05846

Cohomological dimension, Lyubeznik numbers, and connectedness properties in mixed characteristic

Daniel J. Hernández·Luis Núñez-Betancourt·Felipe Pérez·Emily E. Witt
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Abstract

We establish a "second vanishing theorem" for local cohomology modules over regular rings of unramified mixed characteristic, which relates the connectedness of the spectrum of a ring with the vanishing of local cohomology. Applying this, and new results on the mixed characteristic Lyubeznik numbers, we further study connectedness properties of the spectra of a certain class of rings.

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Daniel J. Hernández, Luis Núñez-Betancourt, Felipe Pérez, Emily E. Witt. 2016-09-19. Cohomological dimension, Lyubeznik numbers, and connectedness properties in mixed characteristic. https://arxiv.org/abs/1609.05846

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