We are pleased to announce the winners of the two poster awards that Entropy sponsored at the Quantum Information Revolution: Impact to Foundations (QIRIF) in Växö (Sweden) on 10–13 June, 2019. The Editor-in-Chief of Entropy, Prof. Dr. Kevin H. Knuth (University at Albany, NY, USA), granted the certificate to the winners.

1st prize (350 CHF, certificate)
"Local Observer-Independent Facts is a weaker assumption than Local Causality" by Anibal Utreras-Alarcon

We study the set of correlations that satisfy the assumptions of freedom of choice, locality (defined as parameter independence) and observer-independent facts. The set of these assumptions was previously shown to be in contradiction with the prediction of quantum theory by Caslav Brukner (Brukner, Entropy 20, 350 (2018)). We found that these correlations are not only different from quantum correlations, but also from those that are characterized by a local hidden-variables model. Indeed, the set of local observer-independent facts correlations is a superset of the set of the local hidden-variables model.

2nd prize (150 CHF, certificate)
"Using the Quantum Zeno Effect to Create Phase Contrast in Electron Microscopy" by Pieter Kruit

The concept of interaction-free measurements as proposed by Elitzur and Vaidman [1] for photons, should also work with electrons [2]. When built into a transmission electron microscope [3], this may lead to imaging modes with reduced damage. In our scheme, the electron wave is split by an amplitude splitter in a large component (the reference beam) that passes through a hole in the specimen and a small component (the sample beam) that passes through the sample. After the passage, both beams are cycled back to the amplitude splitter and the process is repeated. If the sample has no effect on the beam, the amplitude in the sample beam slowly builds up until it has the full intensity after m cycles. If the sample does have an influence, either on the amplitude or on the phase, the intensity transfer is disturbed by the quantum Zeno effect, and the intensity stays in the reference beam. Using the model explained in [4], the signals in the reference beam (R) and the sample beam (S) can be calculated as a function of the phase change in the specimen. To get an impression of what kind of images our method would produce, we simulate electron microscopy images of proteins and show “iso-phase lines” or “iso-phase areas” while only causing damage around these lines or in these areas.

[1] Elitzur, A.C.; Vaidman, L. Found. Phys. 1993, 23, 987–997.
[2] Putnam, W.; Yanik, M. Phys. Rev. A 2009, 80, 040902.
[3] Kruit, P.; R.G. Hobbs; C.-S. Kim; Y. Yang; V.R. Manfrinato; J. Hammer; S. Thomas; P. Weber; B. Klopfer; C. Kohstall; T. Juffmann; M.A. Kasevich; P. Hommelhoff; K.K. Berggren. Ultramicroscopy 2016, doi:10.1016/j.ultramic.2016.03.004.
[4] Thomas, S.; Kohstall, C.; Kruit, P.; Hommelhoff, P. Phys. Rev. A 2014, 90, 053840.
[5] The authors acknowledge funding from the Gordon and Betty Moore Foundation and the Netherlands Organization for Scientific Research (NWO).