Blowing-ups Describing the Polarization Change of Moduli Schemes of Semistable Sheaves of General Rank
نویسنده
چکیده
Let H and H ′ be two ample line bundles over a smooth projective surface X , and M(H) (resp. M(H )) the coarse moduli scheme of H-semistable (resp. H -semistable) sheaves of fixed type (r, c1, c2). We construct a sequence of blowing-ups which describes how M(H) differs from M(H ) not only when r = 2 but also when r is arbitrary. Means we here utilize are elementary transforms and the notion of a sheaf with flag.
منابع مشابه
A Sequence of Blowing-ups Connecting Moduli of Sheaves and the Donaldson Polynomial under Change of Polarization
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تاریخ انتشار 2008