Abstract
We study the geometry of the secant and tangential variety of a cominuscule and minuscule variety, e.g. a Grassmannian or a spinor variety. Using methods inspired by statistics we provide an explicit local isomorphism with a product of an affine space with a variety which is the Zariski closure of the image of a map defined by generalized determinants. In particular, equations of the secant or tangential variety correspond to relations among generalized determinants. We also provide a representation theoretic decomposition of cubics in the ideal of the secant variety of any Grassmannian. (C) 2015 Elsevier Inc. All rights reserved.
| Original language | English |
|---|---|
| Pages (from-to) | 288-312 |
| Number of pages | 25 |
| Journal | Linear Algebra and Its Applications |
| Volume | 481 |
| DOIs | |
| Publication status | Published - 15 Sept 2015 |
| MoE publication type | A1 Journal article-refereed |
Funding
The second author is supported by the Narodowe Centrum Nauki grant UMO-2011/01/N/ST1/05424 "Representation theory and secants of homogeneous varieties".
Keywords
- Grassmannian
- Minuscule and cominuscule representation
- Secant variety
- Generalized determinant
- Cumulants
- TANGENTIAL VARIETIES