#### Statistical Mechanics Seminar, V. Mastropietro, "Universal conductivity in graphene; some rigorous results and open problems"

Abstract: Recent experiments have found an universal value for the dynamic conductivity in graphene, fully confirming theoretical predictions based on a non interacting tight binding model. This however poses a problem since one could expect a many body renormalization of the non interacting value of the conductivity due to the interaction. In the presence of weak and short range interactions, a theorem valid for the Hubbard model on the honeycomb lattice ensures that all the interaction corrections to the conductivity are vanishing. The proof is based on a combination of Ward Identities and regularity properties obtained by convergent expansions. Some results for the case of long range interactions will

be also presented.

**Location:**
Fine 224

**Date/Time: **12/07/11
at
2:00 pm
- 12/07/11
at
3:30 pm

**Category: **Statistical Mechanics Seminar

**Department: **Physics