Seminários

Seminário do grupo de Óptica e Informação Quântica

Data: Sexta-Feira 05/10/2018, Sala A5-01, 11 am.

Palestrante: Jacques Pienaar, International Institute of Physics (IIP) -Natal

Título: Causal analysis of Bell inequality violation in classical light

Abstract: Different degrees of freedom of a classical beam of light can exhibit some features of quantum entanglement, enabling classical optical analogies to certain quantum information protocols, and allowing light beams to violate inequalities analogous to Bell, expressed in intensities rather than probabilities. Traditional explanations of this phenomenon focus on the fact that genuine quantumness also requires reduced photon number fluctuations, or that the modes be space-like separated. We analyze this phenomenon from a causal modeling perspective. Causal models have recently been used to argue that Bell inequality violations in quantum systems are a signature of `fine-tuning’. We ask whether the same conclusion also holds for Bell inequality violations of classical light. We determine that the problem is not well-posed unless one draws an explicit link between classical light intensities and probabilistic variables. Depending on how this is done, `fine-tuning' may or may not be a necessary part of the causal explanation.