As we are at the beginning of the second century of quantum physics, we asked four researchers to share their views on new research directions trying to answer old, yet still open, questions in the foundations of quantum theory.
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Acknowledgements
E.G.C. acknowledges L. del Rio, N. Tischler, H. Wiseman, W. Zeng and participants of the Towards Experimental Wigner’s Friends workshop in San Francisco for useful discussions on the LF experimental programme, as well as support from grant no. FQXi-RFP-CPW-2019 from the Foundational Questions Institute and Fetzer Franklin Fund. R.C. acknowledges support from the Serrapilheira Institute (grant no. Serra – 1708-15763) and the Simons Foundation (grant no. 1023171, RC). F.G. would like to thank R. Renner for helpful comments on a first draft of her contribution, and acknowledges support from the Swiss National Science Foundation via the Ambizione Grant PZ00P2-208885. Y.-C.L. is grateful to N. Gisin for the many inspiring discussions on quantum foundations and for introducing to him the exciting topic of entangled measurements, and acknowledges support from the National Science and Technology Council and the National Center for Theoretical Sciences, Taiwan.
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Eric Cavalcanti is an Associate Professor at Griffith University in Queensland, Australia. He has also worked at the University of Sydney and University of Oxford, after a PhD in Physics from the University of Queensland. His research focus is on quantum foundations and quantum information theory, and he has also made contributions to a wide range of fields including philosophy of science, quantum atom-optics and experimental atomic collisions.
Rafael Chaves is a research leader at the International Institute of Physics in Natal, Brazil. Previously, he worked in ICFO and the Universities of Freiburg and Cologne as a postdoctoral researcher. His contributions include quantum computation, communication and machine learning. The focus of his research is on the interface between quantum information and causal inference, developing new tools and concepts to investigate the emergence of non-classical features in quantum networks.
Flaminia Giacomini is an SNSF Ambizione Fellow at ETH Zurich. She received her PhD from the University of Vienna and then held a postdoctoral fellowship at Perimeter Institute for Theoretical Physics. Her research uses quantum information tools to answer fundamental questions at the interface between quantum theory and general relativity. Her research interests span from conceptual consequences of the lack of a classical spacetime, such as quantum time, quantum reference frames and indefinite causality, to the study of the observational implications of the quantum nature of gravity in table-top experiments.
Yeong-Cherng Liang is a professor of physics and a research group leader based at the National Cheng Kung University (NCKU), Taiwan. He received his PhD from the University of Queensland, Australia, in 2008. He then did postdoctoral research at the University of Sydney, the University of Geneva and ETH Zürich, before taking up a faculty position at NCKU in 2015. His expertise is in quantum foundations, especially quantum nonlocality, quantum entanglement and their applications in quantum information.
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Cavalcanti, E.G., Chaves, R., Giacomini, F. et al. Fresh perspectives on the foundations of quantum physics. Nat Rev Phys 5, 323–325 (2023). https://doi.org/10.1038/s42254-023-00586-z
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DOI: https://doi.org/10.1038/s42254-023-00586-z
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