Local states and channels in causal theories


Perinotti, P. (2011). Local states and channels in causal theories. Perimeter Institute. https://pirsa.org/11050058


Perinotti, Paolo. Local states and channels in causal theories. Perimeter Institute, May. 17, 2011, https://pirsa.org/11050058


          @misc{ pirsa_PIRSA:11050058,
            doi = {10.48660/11050058},
            url = {https://pirsa.org/11050058},
            author = {Perinotti, Paolo},
            keywords = {Quantum Foundations},
            language = {en},
            title = {Local states and channels in causal theories},
            publisher = {Perimeter Institute},
            year = {2011},
            month = {may},
            note = {PIRSA:11050058 see, \url{https://pirsa.org}}

Paolo Perinotti University of Pavia


We will analyze different aspects of locality in causal operational probabilistic theories. We will first discuss the notion of local state and local objective information in operational probabilistic theories, and define an operational notion of discord that coincides with quantum discord in the case of quantum theory. Using such notion, we will show that the only theory in which all separable states have null discord is the classical one. We will then analyze locality of transformations, reviewing some general properties of no-signaling channels in causal theories. We will show that it is natural to define transformations on no-signaling channels that cannot be extended to all bipartite channels, and discuss the consequences of this fact on information processing.