A tale of two SUSYs

There are two approaches towards supersymmetry: The conventional approach'', in which the fields appear in the classical action and the stochastic approach’', in which they emerge upon introducing in the action the contribution of a certain determinant. The second approach relies, in particular, on the so-called Nicolai map. The relation between the two approaches hasn’t been clarified and the subject of this contribution is to spell it out. In particular the interpretation proposed by Parisi and Sourlas has remained quite incomplete. The subject of this contribution is to spell out in what way the two approaches complement each other and how the second can provide insights for the first.