| Title:
|
On tangent cones to Schubert varieties in type $E$ (English) |
| Author:
|
Ignatyev, Mikhail V. |
| Author:
|
Shevchenko, Aleksandr A. |
| Language:
|
English |
| Journal:
|
Communications in Mathematics |
| ISSN:
|
1804-1388 (print) |
| ISSN:
|
2336-1298 (online) |
| Volume:
|
28 |
| Issue:
|
2 |
| Year:
|
2020 |
| Pages:
|
179-197 |
| Summary lang:
|
English |
| . |
| Category:
|
math |
| . |
| Summary:
|
We consider tangent cones to Schubert subvarieties of the flag variety $G/B$, where $B$ is a Borel subgroup of a reductive complex algebraic group $G$ of type $E_6$, $E_7$ or $E_8$. We prove that if $w_1$ and $w_2$ form a good pair of involutions in the Weyl group $W$ of $G$ then the tangent cones $C_{w_1}$ and $C_{w_2}$ to the corresponding Schubert subvarieties of $G/B$ do not coincide as subschemes of the tangent space to $G/B$ at the neutral point. (English) |
| Keyword:
|
flag variety |
| Keyword:
|
Schubert variety |
| Keyword:
|
tangent cone |
| Keyword:
|
involution in the Weyl group |
| Keyword:
|
Kostant-Kumar polynomial |
| MSC:
|
14M15 |
| MSC:
|
17B22 |
| idZBL:
|
Zbl 07300189 |
| idMR:
|
MR4162929 |
| . |
| Date available:
|
2021-03-03T08:49:46Z |
| Last updated:
|
2021-03-29 |
| Stable URL:
|
http://hdl.handle.net/10338.dmlcz/148702 |
| . |
| Reference:
|
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| Reference:
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