Open quantum systems (OQS) cannot always be described with the Markov approximation, which requires a large separation of system and environment time scales. In this talk I will give an overview of some recent advances to tackle the dynamics of an OQS beyond the Markov approximation, with special emphasis in hierarchy-based [1,2] and chain mapping-based  approaches. In the latter context, I will discuss the use of a thermofield transformation to describe thermal environments .
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 I. de Vega, J. Phys. A: Math. Theor. 48, 145202 (2015).
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 I. de Vega and M.C. Bañuls, arXiv:1504.07228.
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Date & time: 20/07/2015 at 10:00.
Location: Room P3.10, Mathematics Building, Instituto Superior Técnico, Lisbon.