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Cosmic Bell test probes the reality of quantum mechanics

01 Dec 2020 James Dacey

In this interview, Johannes Handsteiner describes an experiment to test the foundations of quantum mechanics. Handsteiner was part of a team at the Institute for Quantum Optics and Quantum Information (IQOQI) in Vienna, Austria, that designed a Bell test experiment using light from now-ancient quasars. Handsteiner explains why his team went to such lengths to close an important loophole in this famous test designed to rule out the possibility of a classical explanation.

The interview was recorded in 2019 before the COVID-19 pandemic. Handsteiner now works at Quantum Technology Laboratories, a company involved in contract research in the field of Quantum Key Distribution (QKD).

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