Recent content by kmyzzmy

When we want to calculate the n-point function in the position space, it's always very difficult. For example, when we're calculate the 3-point function of \phi^3 theory in position space, we would get an integral \int d^4 z \frac{1}{|z-x_1|^2|z-x_2|^2|z-x_3|^2} It seems hard to integrate it...