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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

If cosmological perturbations in our Hubble sized volume are nongaussian,then they will be coupled to any larger perturbation modes outside our Hubblevolume. This has important consequences for modeling inflation: the scalarpower spectrum and spectral index measured in our Hubble volume would depend onan adjacent background of super Hubble perturbations. In other words, adetection of nongaussianity implies a possible portal to the superhorizon. Bythe same token, ruling out nongaussianity would rule out the possibility thatthe power spectrum's size and running are accidents of super cosmic variance.In this note, we provide a compact derivation of super cosmic variance, surveyrecent results, and show how experimental limits on nongaussianity help to ruleit out.

Beyond the Hubble scale: Super cosmic variance and nongaussianity as a portal to the superhorizon