I'm trying to compute the double Higgs scatter in QFT framework. Is it correct if I use the scalar propagator for this process?
Also I've found that I've four possible diagrams: the three $s,t,u$ channels and the point, $x$ like diagram. So when I try to do the $M$ amplitude I get a something that goes like the inverse product of difference between each Mandlestam variable and the mass of the higgs squared.
Unfortunately in my book I don't find any results to check my calculations.
