Nested Integrals and Rationalizing Transformations

Abstract

A brief overview of some computer algebra methods for computations with nested integrals is given. The focus is on nested integrals over integrands involving square roots. Rewrite rules for conversion to and from associated nested sums are discussed. We also include a short discussion comparing the holonomic systems approach and the differential field approach. For simplification to rational integrands, we give a comprehensive list of univariate rationalizing transformations, including transformations tuned to map the interval $[0,1]$ bijectively to itself.

manuscript of 25 February 2021, in "Anti-Differentiation and the Calculation of Feynman Amplitudes", Springer