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-Julian Wechs and Ognyan Oreshkov from QuIC and Cyril Branciard from the French National Centre for Scientific Research 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. This phenomenon has been known to be possible in theory but widely believed impossible in practice, at least in the known regimes of physics. 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.
+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.
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 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]].
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+<box w=99% nodash|**Cyclic quantum causal models** (Nature Communications, February 2021)>
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+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]].
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+See [[https://www.eurekalert.org/news-releases/783860|press release]].
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