PHYSICAL REGULARIZATION AND FINITENESS OF SUPERSTRING THEORIES
F. Ardalan, H. Arfaei, J. PARVIZI · Modern Physics Letters A · 1986
We provide a regularization procedure for loops in string theories based on the physical picture of joining and splitting strings. This procedure justifies the 1-loop finiteness of superstring theories. To find the regularization, maps from the string world-sheet to the complex plane are studied in detail.