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arXiv · 1602.07187

Essential dimension of group schemes over a local scheme

Dajano Tossici
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Abstract

In this paper we develop the theory of essential dimension of group schemes over an integral base. Shortly we concentrate over a local base. As a consequence of our theory we give a result of invariance of the essential dimension over a field. The case of group schemes over a discrete valuation ring is discussed. Moreover we propose a generalization of Ledet conjecture, which predicts the essential dimension of cyclic $p$-groups in positive characteristic, for finite commutative unipotent group schemes. And we show some results and some consequences of this new conjecture.

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Dajano Tossici. 2016-02-23. Essential dimension of group schemes over a local scheme. https://arxiv.org/abs/1602.07187

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