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

We show that gravity and matter fields are generically entangled, as aconsequence of the local Poincar\'e symmetry. First, we present a generalargument, applicable to any particular theory of quantum gravity with matter,by performing the analysis in the abstract nonperturbative canonical framework,demonstrating the nonseparability of the scalar constraint, thus promoting theentangled states as the physical ones. Also, within the covariant framework, weshow explicitly that the Hartle-Hawking state in the Regge model of quantumgravity is necessarily entangled. Our result is potentially relevant for thequantum-to-classical transition, taken within the framework of the decoherenceprogramme: due to the gauge symmetry requirements, the matter does notdecohere, it is by default decohered by gravity. Generically, entanglement is aconsequence of interaction. This new entanglement could potentially, in form ofan "effective interaction", bring about corrections to the weak equivalenceprinciple, further confirming that spacetime as a smooth four-dimensionalmanifold is an emergent phenomenon. Finally, the existence of thegauge-protected entanglement between gravity and matter could be seen as acriterion for a plausible theory of quantum gravity, and in the case ofperturbative quantisation approaches, a confirmation of the persistence of themanifestly broken gauge symmetry.

Gauge protected entanglement between gravity and matter