Constructing the Virasoro groups using differential cohomology

Abstract

The Virasoro groups are a family of central extensions of ${\mathrm{Diff}}^{+}(S^1)$, the group of orientation-preserving diffeomorphisms of $S^1$, by the circle group $\mathbb{T}$. We give a novel, geometric construction of these central extensions using "off-diagonal" differential lifts of the first Pontryagin class, thus affirmatively answering a question of Freed-Hopkins.

26 pages

References in corpus (2)

• BMS Particles in Three Dimensions
• Homological stability for moduli spaces of disconnected submanifolds, I

Cited by in corpus (1)

• Differential cohomology (encyclopedia article)