Speaker
Description
By now, using differential equations rather than direct integration has become a standard method for computing multi-loop Feynman integrals. The notion of canonical bases, where these differential equations take a particularly simple form, is well understood for integrals that evaluate to multiple polylogarithms. In particular, it is well-known that canonical integrals can be understood as integrals with constant leading singularities, where the latter can be computed purely from the integrands. However, there are many known examples of Feynman integrals that do not evaluate to polylogarithms, where these concepts are more subtle, if defined at all. In this talk, I will elaborate on the connection of integrand analysis, leading singularities and canonical bases beyond polylogarithms, and apply these concepts to self-energies in QED and QCD.