Mathematical Aspects of Quantum Field Theory Lecture Two: Renormalization and Effective Field Theories
چکیده
We concluded the previous lecture by discussing the finite dimensional version of Wick’s lemma, which computes integrals of polynomials against Gaussian measures as a sum over Feynman diagrams. In today’s lecture, we will see how this procedure carries over to the infinite dimensional setting of (perturbative) quantum field theory. It is instructive to work with a concrete example, though all of our analysis applies to more general theories. Consider φ theory in dimension d with classical action given by