# Defining chiral gauge theories on a 2-d lattice

Date and time |
Jan 28, 2013 from 12:10 PM to 01:00 PM |
---|---|

Location | 60 St. George Street, MP 1115 |

Host | Erich Poppitz |

## Yanwen Shang

**
Perimeter Institute
**

Defining chiral gauge theory on a finite lattice has been a
longstanding difficult problem. In the Ginsparg-Wilson formalism, the
very existence of such theories are intriguingly tied to the presence or
absence of gauge anomalies, and the connection arises from a
topological consideration. It has been fully understood that abelian
chiral gauge theories can be defined in this formalism if and only if
the fermion content is anomaly-free. But, for nonabelian gauge theories,
the complete understanding is still missing. In 2-d, significant
simplifications allow one to go a bit further and treat
the nonabelian theories much more easily. In this talk, I will review
the challenge for defining chiral lattice gauge theories in the
Ginsparg-Wilson formalism, discuss the topology of the gauge field
configuration space in 2-d, and explain how the gauge anomaly-free
condition arises as a topological requirement for the theory to be
self-consistent when the gauge group is an arbitrary compact Lie group.

Contact Name | Helen Iyer |
---|---|

Contact Phone | 416-978-7135 |