### At “Geometry, Quantum Fields, and Strings: Categorial Aspects”

#### Posted by Urs Schreiber

This week at Oberwolfach takes place a workshop titled *Geometry, Quantum Fields, and Strings: Categorial Aspects*, organized by Peter Bouwknegt, Dan Freed, Christoph Schweigert.

The workshop’s webpage is here.

Posted at June 8, 2010 12:48 PM UTC
## Orientifold differential cohomology

Close to my heart today was the talk by Greg Moore on his work with Jacques Distler and Dan Freed (which we have talked about before here on various occasions) on the differential cohomology of orientifold backgrounds for string sigma-models.

The slides he pesented are available here: