Difference between a path integral, a Feynman path integral, a Wiener path integral? I am having trouble finding any clear information on path integrals. I am trying to find the difference between a normal path integral, a Feynman path integral and a Wiener path integral and the conditions on each to make a well-defined and calculable integral. Please can someone explain.
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*A (Feynman) path integral is what physicists call any of the functional integrals that pop up in the functional integral (or path integral) approach to quantum mechanics and quantum field theory. I will not exclude the possibility that some might use the qualifer "Feynman" to done some specific integral, but for most physicists a "path integral" and a "Feynman path integral" are the same. Note that you shouldn't confuse this with the Feynman parameter trick, where the integrals appearing might be called "Feynman integrals" by some. The path integral is, in general, not known to be mathematically well-defined, in particular only very rarely in spacetime dimensions greater than 3. For scalar fields (and also some fermionic fields) with polynomial interactions in two dimensions it is known - see the work by Glimm and Jaffe - how to set up a well-defined path integral using the Wightman/Osterwalder-Schrader axioms.

*A Wiener integral is either the integral with respect to the Wiener measure on the classical Wiener space of continuous paths, or the more general notion of the Paley-Wiener integral. It is mathematically well-defined. The relation to path integrals comes about because the quantum mechanical version of the path integral (that of "0+1 dimensional QFT" if you like) is a (conditional) Wiener integral, and therefore mathematically well-defined. 
If you are interested in a detailed exploration of the rigorous mathematics of the path integrals that appear in physics, "Quantum physics - A functional integral point of view" by Glimm and Jaffe is an excellent, if somewhat dense, resource.
