Power sum varieties of quaternary quartics

Moduli and Algebraic Cycles

23 November 13:15 - 14:15

Kristian Ranestad - University of Oslo

The variety of minimal power sum presentations of a homogeneous form is a PGL-invariant that may be used to distinguish forms. In special cases it defines surprising maps between moduli spaces of varieties. I will review old and new results on power sum varieties, and report on recent work with G. and M. Kapustka, M. Stilmann, H. Schenk and B. Yuan on quaternary quartics. In particular, a new map between two 18-dimensional families of quartic surfaces.

Click here to watch the seminar

John Christian Ottem
University of Oslo
Dan Petersen
Stockholm University
David Rydh
KTH Royal Institute of Technology


Dan Petersen


For practical matters at the Institute, send an e-mail to