Tag

Causality

All articles tagged with #causality

Quantum Time Chaos: New Test Supports Indefinite Causal Order
science14 days ago

Quantum Time Chaos: New Test Supports Indefinite Causal Order

A Vienna team extends Bell-test ideas to indefinite causal order, using entangled photons arranged so that the sequence A→B or B→A depends on polarization. The observed correlations differ from local-hidden-variable predictions by 18 standard deviations, suggesting quantum processes can exist in a superposition of temporal orders. However, notable loopholes remain (photon loss, limited separation) and further experiments are needed to close them, though the work points toward broader applications of time-uncertain quantum processes.

"Harmonizing Scientific Methods to Understand Complex Systems: A Unified Framework for Interaction Dynamics"
scientific-research2 years ago

"Harmonizing Scientific Methods to Understand Complex Systems: A Unified Framework for Interaction Dynamics"

This article discusses the unification of pairwise interactions in complex dynamics, focusing on the field of network neuroscience. It highlights the importance of understanding causality in complex systems and references various methods such as Granger causality, transfer entropy, and directed information. The article also mentions the significance of information integration and provides references to related studies and mathematical frameworks.

Causal Inequalities Challenged by Time-Delocalized Variables.
physics3 years ago

Causal Inequalities Challenged by Time-Delocalized Variables.

Researchers have shown that certain processes violating causal inequalities can be realized in the regimes of standard quantum physics, on so-called time-delocalized subsystems. These are physical systems defined by observables that are delocalized over different instants of time, much in the same way as quantum information can be delocalized in space, for instance in quantum error correcting codes. The finding may have far-reaching implications for our understanding of causality in physics.

The evolving truth about Long COVID and its impact on patients.
health3 years ago

The evolving truth about Long COVID and its impact on patients.

Long COVID is not as common or severe as initially feared, with most patients experiencing symptoms that resolve in less than a year. Retrospective cohort studies have shown that it's not easy to prove causality between a particular infection and a symptom. While long COVID is a real illness that has dramatically affected many people's lives, its prevalence does seem significantly less worrisome than originally thought.