Zurek has proposed a http://lanl.arxiv.org/abs/1105.4810v1" (Phys.Rev.Lett.106:250402,2011) based on these assumptions: (i) States “live” in Hilbert spaces (ii) Evolutions (including measurements) are unitary. (o) Hilbert spaces of composite systems have tensor structure. (iii) Immediate repetition of a measurement yields the same outcome. (z) "Envariance also relies on locality of quantum dynamics (i.e., the fact that a unitary operation here cannot change a state there)" Is it correct and satisfactory? What is the BM take on this?