Hořava and Keeler on non-supersymmetric heterotic M-theory

It happens quite frequently that I consider the first paper on the hep-th archive to be the most interesting one. I guess that it's only possible because the community is sensible.

Hořava and Keeler - whom you may remember as the discoverers of non-critical M-theory - discuss the supersymmetry-breaking heterotic M-theory by Hořava and Fabinger and especially its perturbative description. It involves a heterotic string with a single E8 group. If you like E8 representation theory and complicated orbifolds of free fermion theories, you should like the paper.

Also, interesting and clarifying analogies with the work of Swanson and Hellerman emerge. Logarithmic CFTs - whose OPEs are allowed to have logarithmic singularity structures - turn out to be relevant for tachyon condensation.