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 Recently, it also has contributed to establish the fundamental limit on the transmission rate via Gaussian bosonic channels (the quantum extension of Shannon's famous channel capacity formula), and has discovered a quantum two-photon interference effect in the amplification of light akin to the Hong-Ou-Mandel effect.
-It currently holds two patents, and has published numerous scientific papers, among which two in the journal //Nature//, one in //Nature Physics//, two in //Nature Photonics//, and two in //Nature Communications//.
+It currently holds two patents, and has published numerous scientific papers, among which two in the journal //Nature//, one in //Nature Physics//, two in //Nature Photonics//, and three in //Nature Communications//.
 //Nicolas J. Cerf, group leader.//
-<box w=99% nodash|**JOB OPENING : Postdoctoral position in quantum foundations** >
+<box w=99% nodash|**JOB OPENING : Postdoctoral position in quantum foundations and information** >
-Applications are invited for a postdoctoral position in quantum foundations. The researcher will work with Dr. Ognyan Oreshkov within the framework of the consortium project “The Quantum Information Structure of Spacetime ([[http://www.qiss.fr|QISS]])”, funded by the John Templeton Foundation. This is a multinational research effort at the intersection of quantum gravity, quantum computing, and quantum foundations, which aims to understand the structure of spacetime from an informational perspective through collaboration between experts from different fields. The position in Brussels will investigate the concept of causal structure in quantum theory, with particular focus on approaches to quantum theory in the absence of predefined causal structure, the notion of causal nonseparability and its relevance at the intersection of quantum mechanics and gravity, as well as the link between causal structure and quantum reference frames.
+Applications are invited for a postdoctoral position in quantum foundations and quantum information. The researcher will work with Dr. Ognyan Oreshkov on topics ranging from entanglement to causal structures and quantum reference frames. The position is for up to two years, finishing at the end of 2025. For application instructions, see [[https://www.quantiki.org/position/postdoctoral-position-quantum-foundations-and-information-ulb|announcement]].
-Please direct informal enquiries to [[oreshkov@ulb.ac.be|Dr. Ognyan Oreshkov]].
+Please direct informal enquiries to [[ognyan.oreshkov@ulb.be|Dr. Ognyan Oreshkov]].
 </box>
+<box w=99% nodash|**Time-delocalised variables violating causal inequalities** (Nature Communications, March 2023)>
+<box left w=125px noborder> {{:time-delocalised.jpg?150|}}
+</box>
+<box right w=80% noborder>
+Julian Wechs and Ognyan Oreshkov from QuIC and Cyril Branciard from the CNRS have shown for the first time that an exotic type of process violating causal inequalities can be realised with known physics. A violation of a causal inequality proves under theory-independent assumptions that certain variables in an experiment cannot be assigned a definite causal order. The new study, published in [[https://www.nature.com/articles/s41467-023-36893-3|Nature Communications]], shows that such processes can be realised in standard quantum mechanics using variables delocalised in time. The finding may have far-reaching implications for our understanding of causality in physics.
+\\
+See [[https://actus.ulb.be/fr/presse/communiques-de-presse/recherche/des-variables-delocalisees-dans-le-temps-allant-a-lencontre-des-inegalites-causales|press release]].
+</box>
+</box>
+<box w=99% nodash|**Cyclic quantum causal models** (Nature Communications, February 2021)>
+<box left w=125px noborder> {{:causalloops.jpg?160|}}
+</box>
+<box right w=80% noborder>
+Ognyan Oreshkov from QuIC and colleagues Jonathan Barrett and Robin Lorenz from the University of Oxford have developed a theory of causality in quantum theory, according to which cause-effect relations can sometimes form cycles. This theory offers a novel understanding of exotic processes in which events do not have a definite causal order. The study has been published in [[https://www.nature.com/articles/s41467-020-20456-x|Nature Communications]].
+\\
+See [[https://www.eurekalert.org/news-releases/783860|press release]].
+</box>
+</box>
+<box w=99% nodash|**Quantum interference in time** (Proceedings of the National Academy of Sciences, December 2020)>
+<box left w=125px noborder> {{:hom-1.png?130|}}
+</box>
+<box right w=80% noborder>
+Nicolas Cerf from QuIC and Michael Jabbour from the University of Cambridge have uncovered an unsuspected quantum interference mechanism, which originates from the indistinguishability of identical bosons in time. The famous Hong–Ou–Mandel effect describes the “bunching” of identical bosons at the output of a half-transparent beam splitter resulting from the symmetry of the wave function. The study, published in the [[https://www.pnas.org/doi/full/10.1073/pnas.2010827117|Proceedings of the National Academy of Sciences]], establishes that this effect turns, under partial time reversal, into an interference effect in a quantum amplifier that can be ascribed to time-like indistinguishability (bosons from the past and future cannot be distinguished). This hitherto unknown effect is a genuine manifestation of quantum physics and may be observed whenever two identical bosons participate in Bogoliubov transformations, which play a role in many facets of physics.
+\\
+See [[https://phys.org/news/2020-12-quantum.html|press release]].
+</box>
+</box>
 <box w=99% nodash|**Ognyan Oreshkov** joins QuIC as a permanent F.R.S.-FNRS researcher!>