Sliding functor and polarization functor for multigraded modules

Kohji Yanagawa

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arXiv · 1010.4112

Sliding functor and polarization functor for multigraded modules

Kohji Yanagawa

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Abstract

We define "sliding functors", which are exact endofunctors of the category of multi-graded modules over a polynomial ring. They preserve several invariants of modules, especially the (usual) depth and Stanley depth. In a similar way, we can also define the "polarization functor". While this idea has appeared in papers of Bruns-Herzog and Sbarra, we give slightly different approach. Keeping these functors in mind, we treat simplicial spheres of Bier-Murai type.

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Kohji Yanagawa. 2010-10-20. Sliding functor and polarization functor for multigraded modules. https://arxiv.org/abs/1010.4112

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