Topic: The universal structure of large logarithms in scattering amplitudes and cross sections 

Speaker: Prof. Jian Wang

Coordinates:PCFT C1124, 4pm, Thursday, Apr. 29

Abstract: The scattering amplitudes and cross sections are the central objects in theories of fundamental interactions, and play special roles in testing any theory with experiments. Though there is significant progress in our understanding of their structures, it is still hard to calculate them precisely, especially for processes with multiple scales. However, they turn out to be dominated by large logarithms in the case that a large scale hierarchy exists. In the leading power factorization scheme, these logarithms are fully controlled by universal anomalous dimensions of effective operators. At subleading power, the factorization scheme is often plagued by end-point singularities. The anomalous dimension may also contain large logarithms in itself. It is of great importance to understand these new structures more deeply and clearly.