Dimensional regularization

In theoretical physics, dimensional regularization is a method introduced by Juan José Giambiagi and Carlos Guido Bollini as well as – independently and more comprehensively – by Gerard 't Hooft and Martinus J. G. Veltman for regularizing integrals in the evaluation of Feynman diagrams; in other words, assigning values to them that are meromorphic functions of a complex parameter d, the analytic continuation of the number of spacetime dimensions. Dimensional regularization writes a Feynman integral as an integral depending on the spacetime dimension d and the squared distances (xi−xj)2 of the spacetime points xi, ...

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