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Logic and Computation Seminar

Monday, January 30, 2017 - 3:30pm

William Simmons

University of Pennsylvania


University of Pennsylvania


Ultraproducts and other nonconstructive tools often yield existence results without giving explicit values. We examine the interplay of such arguments with "proof mining" techniques that systematically extract effective information even when it is not apparent. Our main application is to differential algebra, where the existence and nature of uniform bounds are more elusive than in the algebraic case. This is joint work with Henry Towsner.