Not sure how this relates. Strangely, the Wikipedia article doesn’t even mention that other article by De Concini–Procesi, the one mentioned in #2 above, which actually talks about being “wonderful”. In that other article there is, a priori, no group action at all.
]]>Yes, odd.
Is Wikipedia general enough?
]]>In algebraic group theory, a wonderful compactification of a variety acted on by an algebraic group is a -equivariant compactification such that the closure of each orbit is smooth.
added pointer to
Corrado de Concini, Claudio Procesi, Wonderful models of subspace arrangements, Selecta Mathematica, New Series Vol. 1, No. 3, 1995 (pdf)
Eva Maria Feichner, De Concini–Procesi Wonderful Arrangement Models: A Discrete Geometer’s Point of View, Math. Sci. Res. Inst. Publ 52, 2005 (pdf)
(According to mechanical string search for “wonderful” in these articles, neither of them ever mentions that “wonderful” is used here as a technical term, and how. Isn’t that a little bizarre?)
]]>a stub, just to finally make that link at compactification work
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