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

A model in which pointlike defects are randomly embedded in Minkowskispacetime is considered. The distribution of spacetime defects is constructedto be Lorentz-invariant. It does not introduce a preferred reference frame,because it is based on a sprinkling process. A field-theoretic action for thephoton and a fermion is set up, in which the photon is assumed not to couple tothe defects directly, but via a scalar field. We are interested in signs forLorentz violation caused by the spacetime defects, which are expected to revealthemselves in the photon sector. A modification of the photon dispersionrelation may result as a quantum effect and we compute it at leading orderperturbation theory.  The outcome of the calculation is that the photon dispersion law remainsconventional, if the defect distribution is dense, homogeneous, and isotropic.This result sheds some new light on Lorentz violation in the framework of asmall-scale structure of spacetime. It shows that Lorentz invariance can bepreserved even in the presence of a spacetime structure that is supposed toemerge at the Planck scale. This conclusion has already been drawn on generalgrounds in other publications, where the current paper delivers a demonstrationby a direct computation in a simple model.

A simple model of pointlike spacetime defects and implications for photon propagation