The Paul Ehrenfest Best Paper Award for Quantum Foundations recognizes outstanding and influential research contributions to the foundations of quantum physics. The aim of the award is to raise awareness for the field of quantum foundations, and to draw attention to new and interesting achievements in this area without delay. It is awarded for the most significant paper in foundations of quantum physics, theoretical or experimental, published in a peer-review journal in the five calendar years prior to the prize call (i.e., this year we accept submissions published between Jan 1, 2016 - Dec. 31, 2020).  Other than that, papers from all areas in the foundations of quantum physics, and by authors of any background, will be eligible to receive the award, see the rules.

The winner of the 2021 Paul Ehrenfest Best Paper Award for Quantum Foundations is:

The committee awarded the prize to Xu et al. for “proving a long standing conjecture concerning the minimal construction that can be used in a proof of the Kochen-Specker theorem; namely, for proving that the 18-vector construction of Cabello, Estebaranz, and García-Alcaine employs the minimal set of ideal measurements sufficient to show that quantum mechanics cannot be reconciled with any classical models that are noncontextual.”