Top quark threshold production in $\gamma \gamma$ collisions: current theoretical issues

Abstract

The top quark-antiquark pair threshold production at future High Energy Photon Colliders is considered in view of the recent advances in the theoretical description of the nonrelativistic heavy quark dynamics.

Comments: 6 pages LaTeX, talk presented at the International Workshop on High Energy Photon Colliders DESY, Hamburg, Germany, June 14-17, 2000