Rationality, Contextuality, and Extended Probabilities

Seminar | 336 | 14:00

José Acacio de Barros,

San Francisco State University


Rationality is often associated with classic theory of probability, which is built on top of a Boolean structure of events. However, some experimental conditions, both in physics and in the social sciences, do not permit a classic description, as this description would lead to logical contradictions. The reason for such contradictions are that experimental outcomes depend non-trivially on the context, i.e. they are contextual. In this talk we will discuss such examples and then show how classic probability theory can be modified to include contextual systems.


José Acacio de Barros physicist and philosopher with contributions to the foundations of quantum mechanics, quantum cosmology, and quantum cognition. Dr. de Barros received his PhD in Physics from the Centro Brasileiro de Pesquisas Fisicas (CBPF) in 1991 under the supervision of Francisco Antonio Doria and Antonio Fernandes da Fonseca Teixeira (he was also informally under the supervision of Newton da Costa). Since 2007 he has been in the Liberal Studies faculty of San Francisco State University. Before going to San Francisco, he was an Associate Professor of Physics at the Federal University at Juiz de Fora, Brazil, and he was a Visiting Associate Professor at the Center for the Study of Language and Information at Stanford University, and has also held visiting positions at the Centro Brasileiro de Pesquisas Fisicas.

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