String states, loops and effective actions in noncommutative field theory and matrix models

Understand

Refining previous work by Iso, Kawai and Kitazawa, we discuss bi-local string states as a tool for loop computations in noncommutative field theory and matrix models.

• Defined in terms of coherent states, they exhibit the stringy features of noncommutative field theory.
• This leads to a closed form for the 1-loop effective action in position space, capturing the long-range non-local UV/IR mixing for scalar fields.
• The formalism applies to generic fuzzy spaces.