We look at perturbative properties of noncommutative field theories on R^d and find infrared behavior contrary to naive expectations. We find IR singularities even when the theory is massive, and show that these are associated with the highest momentum modes of the original field. This intriguing mixing of the infrared and the ultraviolet is remeniscent of effects familiar from string theory.

Monday, March 13th 2000, 15:40
Ernest Rutherford Physics Building, room 305