Green’s Functions for Translation Invariant Star Products

2015, September 28
Fedele Lizzi, Manolo Rivera, Patrizia Vitale
Mod.Phys.Lett. A30 (2015) 36, 1550194 http://dx.doi.org/10.1142/S0217732315501941
  1508.02575.pdf

We calculate the Green functions for a scalar field theory with quartic interactions for which the fields are multiplied with a generic translation invariant star product. Our analysis involves both noncommutative products, for which there is the canonical commutation relation among coordinates, and nonlocal commutative products. We give explicit expressions for the one-loop corrections to the two and four point functions. We find that the phenomenon of ultraviolet/infrared mixing is always a consequence of the presence of noncommuting variables. The commutative part of the product does not have the mixing.