**5. Concluding Remarks**

The main contribution in our work is that we have demonstrated that the initial stage of quantum measurement can be described within reversible quantum mechanics. The key components are (i) a scattering theory formulation with inverse processes that both guarantee unitarity and allow for a non-linear mechanism leading to the bifurcation; and (ii) a statistical analysis that reveals how initial states that are efficient in leading to a transition to a final state have a selective advantage and how this results in the correct probabilities of the measurement results as stated by Born's rule.

In our description, we want the system *A* to be big enough for a bifurcation to take place, i.e., for Ξ = *Nχ*<sup>2</sup> to be sufficiently large. Our idea has been to follow the qualitative recipe given by Bell who formulated a principle concerning the position of the Heisenberg cut [10], i.e., the boundary of the system *A*, interacting with *μ* according to quantum dynamics (Ref. [10], p.124):
