English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Nonlocality, as demonstrated by the violation of Bell inequalities, enablesdevice-independent cryptographic tasks that do not require users to trust theirapparatus. In this article, we consider devices whose inputs are spatiotemporaldegrees of freedom, e.g. orientations or time durations. Without assuming thevalidity of quantum theory, we prove that the devices' statistical responsemust respect their input's symmetries, with profound foundational andtechnological implications. We exactly characterize the bipartite binaryquantum correlations in terms of local symmetries, indicating a fundamentalrelation between spacetime and quantum theory. For Bell experimentscharacterized by two input angles, we show that the correlations are accountedfor by a local hidden variable model if they contain enough noise, butconversely must be nonlocal if they are pure enough. This allows us toconstruct a "Bell witness" that certifies nonlocality with fewer measurementsthan possible without such spatiotemporal symmetries, suggesting a new class ofsemi-device-independent protocols for quantum technologies.

Semi-device-independent information processing with spatiotemporal degrees of freedom