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arXiv · 0912.1474

Hassett-Tschinkel correspondence: Modality and projective hypersurfaces

Ivan V. Arzhantsev·Elena V. Sharoyko
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Abstract

B. Hassett and Yu. Tschinkel (1999) introduced a remarkable correspondence between generically transitive actions of a commutative unipotent algebraic group G and finite-dimensional local algebras. In this paper we develop Hassett-Tschinkel correspondence and calculate modality of generically transitive G-actions on projective spaces, classify actions of modality one, and characterize generically transitive G-actions on projective hypersurfaces of given degree. In particular, actions on degenerate projective quadrics are studied.

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Ivan V. Arzhantsev, Elena V. Sharoyko. 2009-12-08. Hassett-Tschinkel correspondence: Modality and projective hypersurfaces. https://arxiv.org/abs/0912.1474

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