Equidimensional actions of algebraic tori
Annales de l'Institut Fourier, Tome 45 (1995) no. 3, pp. 681-705.

Soit X une variété affine conique factorielle sur un corps algébriquement clos de caractéristique zéro. Nous considérons les actions équidimensionnelles, algébriques, et stables d’un tore algébrique sur X qui sont compatibles avec la structure conique. Nous montrons que de telles actions sont colibres et que les nilcônes de X qui lui sont associés sont des intersections complètes.

Let X be an affine conical factorial variety over an algebraically closed field of characteristic zero. We consider equidimensional and stable algebraic actions of an algebraic torus on X compatible with the conical structure. We show that such actions are cofree and the nullcones of X associated with them are complete intersections.

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     author = {Nakajima, Haruhisa},
     title = {Equidimensional actions of algebraic tori},
     journal = {Annales de l'Institut Fourier},
     pages = {681--705},
     publisher = {Association des Annales de l{\textquoteright}institut Fourier},
     volume = {45},
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Nakajima, Haruhisa. Equidimensional actions of algebraic tori. Annales de l'Institut Fourier, Tome 45 (1995) no. 3, pp. 681-705. doi : 10.5802/aif.1470. http://www.numdam.org/articles/10.5802/aif.1470/

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