Tuesday, March 7, 2017 - 1:50pm to 2:50pm
Cockins Hall 240
Title: Mining effective information from nonconstructive proofs in differential algebra
Speaker: William Simmons (University of Pennsylvania)
Abstract: 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.