Detecting orbits along subvarieties via the moment map
نویسنده
چکیده
By moduli we mean the set of points up to the equivalence of lying in the same G orbit. More generally, we are interested in understanding W up to G-equivalence; here G does not preserve W . We study this question when W is smooth and there exists a reductive subgroup H of G which measures the G-action along W . The notion of measuring the G-action is by means of the moment map and we say that G is H-detected along W if mG(w) ∈ h = Lie H for w ∈ W , where mG is the moment map of the G action (see Section 1). Our main result is the following.
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تاریخ انتشار 2008