Harvard Quantum Initiative Special Seminar

Thursday, April 18

4:00 PM

Jefferson 250

Elie Wolfe (Perimeter Institute)

Quantum Nonlocality as a challenge to Classical Causality: How Bell’s Theorem is advancing Causal Inference and vice versa.

A signature example of the nonclassicality of quantum theory is codified in Bell's Theorem, which certifies the nonlocal correlations arising from product measurements on an entangled quantum state as defying any classical explanation.  I'll interpret Bell's Theorem as a statement about the existence of nonclassical "common causes." By considering novel causal scenarios, beyond Bell scenarios, we gain insight into the fundamental quantum nature of cause and effect. I'll show how machine learning (causal discovery algorithms) are crashed by quantum statistics, and I'll discuss my own effort to separate quantum correlations from their classical counterparts in general causal structures. Our approach (unexpectedly) provides a complete solution for classical causal inference, thereby substantially advancing that statistical discipline. Finally, I'll explore quantifying genuinely multipartite entanglement by asking which sorts of quantum causal structures a given state could have arisen from. Based primarily on arXiv:1609.00672, though also drawing on arXiv:1707.06476 and arXiv:1903.06311, as well as unpublished results.

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Clare Ploucha

Administrative Program Manager

Max Planck/Harvard Research Center for Quantum Optics

Department of Physics

17 Oxford Street, Jefferson 357

Cambridge, MA 02138

P: 617-495-3388