Regular Seminar Inaki Garcia Etxebarria (MPI, Munich)
I will show how to construct the familiar heterotic NS5 brane as a topological soliton in a supercritical version of heterotic string theory. Closed string tachyon condensation removes the extra dimensions, leaving the NS5 in 10d, in a process highly reminiscent of the K-theoretical description of type II D-branes, but linking non-trivial gauge bundles and geometry. The construction requires a modification of the anomalous Bianchi identity for H_3 in supercritical heterotic string theory. I will give various proofs for the existence of this modification.