Topology Seminar: Robert Raussendorf

Contextuality is a property of quantum mechanics that sets it apart from classical physics. Recently, it has been established as a necessary ingredient that any quantum computation must have in order to provide a speedup over conventional classical computation [1], [2]. It has thus become a resource.

In my talk, I will first review the notion of quantum contextuality, and then explain how it is a useful commodity in quantum computation---for the models of quantum computation with magic states and measurement-based quantum computation (MBQC). I’ll end with a cohomological picture underlying MBQC and contextuality [3], which is a focus of current research in my group.

[1] M. Howard et al., Nature (London) 510, 351 (2014).

[2] R. Raussendorf, Phys. Rev. A 88, 022322 (2013).

[3] C. Okay et al., Quantum Information and Computation 17, 1135-1166 (2017).