Some computations of Donaldson-Thomas invariants
-- Wei-Ping Li

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I will talk about the joint works with Qin, S. Katz and Hu on
computations of Donaldson-Thomas invariants. The first of these
results studies the moduli space of ideal sheaves on a 3-fold
admitting a smooth fibration over a surface with one free
moving point and the one-dimensional component supported on
fibers. We will discuss the change of the invariants under the
blowup at a point, simple flops and extremal transitions. We
will present the case of rank-two stable bundles.