Comment on 'Uniqueness of the Equation for Quantum State Vector   Collapse' [arXiv:1303.4284]
  A diffusive stochastic Schr\"odinger equation (SSE) is shown for the first time, such that contributes to a non-completely positive dynamics. This contradicts to a recent Letter [arXiv:1303.4284] claiming that SSEs, under most general conditions, enforce complete-positivity. The general form and parametrization of the SSE in the Letter is different from an alternative simpler result, the difference is shown to be completely redundant because of the gauge-freedom of the state vector's phase. 
Lajos Di\'osi
quant-ph math-ph math.MP