Uncovering the history of cosmic inflation from anomalies in cosmic microwave background spectra

Matteo Braglia; Xingang Chen; Dhiraj Kumar Hazra

doi:10.1140/epjc/s10052-022-10461-3

2023 Impact factor 4.2

Particles and Fields

Open Access

Eur. Phys. J. C (2022) 82: 498
https://doi.org/10.1140/epjc/s10052-022-10461-3

Letter

Uncovering the history of cosmic inflation from anomalies in cosmic microwave background spectra

Matteo Braglia¹^,2^a, Xingang Chen³ and Dhiraj Kumar Hazra²^,4

¹ Instituto de Fisica Teorica, Universidad Autonoma de Madrid, 28049, Madrid, Spain
² INAF/OAS Bologna, via Gobetti 101, 40129, Bologna, Italy
³ Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, 02138, Cambridge, MA, USA
⁴ The Institute of Mathematical Sciences, HBNI, CIT Campus, 600113, Chennai, India

^a matteo.braglia2@unibo.it

Received: 14 April 2022
Accepted: 22 May 2022
Published online: 30 May 2022

Abstract

We propose an inflationary primordial feature model that can explain both the large and small-scale anomalies in the currently measured cosmic microwave background anisotropy spectra, revealing a clip of adventurous history of the Universe during its primordial epoch. Although the model is currently statistically indistinguishable from the Standard Model, we show that planned observations such as the Simons Observatory, LiteBIRD and CMB-S4 will complement each other in distinguishing the model differences due to their accurate E-mode polarization measurements, offering very optimistic prospects for a detection or exclusion. The model predicts a signal of classical primordial standard clock, which can also be used to distinguish the inflation and alternative scenarios in a model-independent fashion.

© The Author(s) 2022

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