I take a course this semester on QFT, which deals much with constructive quantum field theory. Some of its topics so far involve relationships between non-Gaussian probability measures and Feynman path integrals and so on. While I am totally new to the subject of QFT (I only have some basic ideas of classical mechanics, classical field theory and quantum mechanics in terms of physics, with knowledge in geometry, topology and analysis for a 2nd year graduate student), I found myself totally lost in the study of that course. On the other hand, my professor tends to talk about everything in a rather hand-waving way with neither strict definitions nor proofs, which made my struggling even worse. Now I have to come for help: are there any references on constructive quantum field theory that would save me out of these? I expect to see clear definitions and basic introductions so that I can enter this field without the trouble of getting myself familiar with the most fundamental stuff firstly. Thank you!

I am taking a course this semester on QFT, which deals much with constructive quantum field theory. Some of its topics so far involve relationships between non-Gaussian probability measures,Feynman path integrals and so on. While I am totally new to the subject of QFT (I only have some basic ideas of classical mechanics, classical field theory and quantum mechanics in terms of physics, with knowledge in geometry, topology and analysis for a 2nd year graduate student), I found myself totally lost in the study of that course. On the other hand, my professor tends to talk about everything in a rather hand-waving way with neither strict definitions nor proofs, which made my struggling even worse. Now I have to come for help: are there any references on constructive quantum field theory that would save me out of these? I expect to see clear definitions and basic introductions so that I can enter this field without the trouble of getting myself familiar with the most fundamental stuff firstly. Thank you!