Ultraviolet and Infrared freedom from string amplitudes
arXiv:hep-th/9907205 · doi:10.1088/1126-6708/1999/10/018
Abstract
The infinite tension limit of string amplitudes is examined with some care, identifying the part responsible of diamagnetic behaviour as well as a peculiar paramagnetic {\em tachyon magnifying} responsible of asymptotic freedom. The way string theory represents abelian gauge theories is connected with the non-planar reggeon/pomeron amplitude and a nontrivial beta function is found in the low energy limit of a single D-brane.
LaTeX, 20 pages, 4 figures, two references added