# A sufficient condition for complete positivity

Date:

Friday, February 6, 2015

Room:

204

Speaker:

Matteo Caiaffa

Abstract:

The evolution equations of the statistical operator are (often) subject to the natural request of complete positivity (CP). This property is guaranteed only if the master equation has a particular form, called Lindblad. When the Lindblad form is missing, the only way to check CP is to solve an eigenvalues problem, which in general is not a pleasant task. In order to find an easier condition to infer CP, we exploit the definition of completely positive dynamical maps. Then, by the mean of a certain commutativity property, we are allowed to work at the level of the wavefunction rather than that of the statistical operator.The result is that asking for a CP master equation is equivalent to the weaker request of having a norm preserving stochastic differential equation.

References:

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