Chiral gauge theories, like the standard model, have lacked a non-perturbative regulator since their inception despite numerous attempts at finding one. One of the challenges in using a lattice regulator for this purpose lies in our inability to isolate a single Weyl fermion. In recent work by Kaplan, it was shown that a single massless Weyl fermion can emerge as an edge state in a theory of a massive Dirac fermion on a disc. I discuss how this construction can be realized on the lattice and removes a significant obstacle for regulating chiral gauge theories.
Raza Sabbir Sufian, Manu Kurian