Speaker
Shu-Heng Shao
(Massachusetts Institute of Technology)
Description
We present an explicit Hamiltonian that realizes an exact lattice chiral U(1)_V x U(1)_A recently proposed. Nielsen-Ninomiya-type no-go theorems are evaded by using lattice bosons rather than fermions. The continuum limit is a compact boson field theory with an axion-like coupling. While U(1)_V shifts the lattice scalar, U(1)_A acts on short axion string excitations. We demonstrate the chiral anomaly by showing that U(1)_A is broken when U(1)_V is gauged. Finally, gauging either U(1)_V and U(1)_A leads to lattice non-invertible and 2-group symmetries, respectively.
Author
Shu-Heng Shao
(Massachusetts Institute of Technology)