Two Orbits: When Is One in the Closure of the Other?

V. L. Popov

Trudy Matematicheskogo Instituta imeni V.A. Steklova, Multidimensional algebraic geometry, Tome 264 (2009), pp. 152-164.

Résumé

Let $G$ be a connected linear algebraic group, let $V$ be a finite dimensional algebraic $G$-module, and let $\mathcal O_1$ and $\mathcal O_2$ be two $G$-orbits in $V$. We describe a constructive way to find out whether or not $\mathcal O_1$ lies in the closure of $\mathcal O_2$.

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