UC Davis Mathematics

Mathematics Colloquia and Seminars

Return to Colloquia & Seminar listing

Spectrahedra and their Shadows

Algebra & Discrete Mathematics

Speaker: Bernd Sturmfels, University of California, Berkeley
Related Webpage: https://math.berkeley.edu/~bernd/
Location: 2112 MSB
Start time: Thu, Apr 23 2015, 4:00PM

This lecture concerns the algebraic geometry that underlies semidefinite programming. After a brief discussion of quartic spectrahedra in 3-space, we focus on spectrahedral shadows, that is, convex sets representable by linear matrix inequalities. We characterize the polynomials that vanish on the boundary of a spectrahedral shadow when the defining matrices are generic. The colorful pictures shown in this lecture can be enjoyed by everyone.