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On the notion of canonical dimension for algebraic groups

G. Berhuy·Z. Reichstein
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Abstract

We define and study a new numerical invariant of an algebraic group action which we call the canonical dimension. We then apply the resulting theory to the problem of computing the minimal number of parameters required to define a generic hypersurface of degree d in P^{n-1}.

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G. Berhuy, Z. Reichstein. 2005-05-31. On the notion of canonical dimension for algebraic groups. https://arxiv.org/abs/math/0404391

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