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Some remarks on varieties with degenerate Gauss image

Emilia Mezzetti·Orsola Tommasi
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Abstract

We consider projective varieties with degenerate Gauss image whose focal hypersurfaces are non-reduced schemes. Examples of this situation are provided by the secant varieties of Severi and Scorza varieties. The Severi varieties are moreover characterized by a uniqueness property.

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Emilia Mezzetti, Orsola Tommasi. 2003-04-09. Some remarks on varieties with degenerate Gauss image. https://arxiv.org/abs/math/0304127

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