In the recent econophysics literature, the use of functional integrals is widespread for the calculation of option prices. In this paper, we extend this approach in several directions by means of δ-function perturbations. First, we show that results about infinitely repulsive δ-function are...

In spite of the power of the Black & Scholes option pricing method, there are situations in which the hypothesis of a lognormal model is too restrictive. One possibility to deal with this problem, consists of a weaker hypothesis, fixing only successive moments and eventually the mode of the...