New physics from the polarized light of the cosmic microwave background

E Komatsu - Nature Reviews Physics, 2022‏ - nature.com
The current cosmological model requires new physics beyond the standard model of
elementary particles and fields, such as dark matter and dark energy. Their nature is …

The weak gravity conjecture and emergence from an ultraviolet cutoff

B Heidenreich, M Reece, T Rudelius - The European Physical Journal C, 2018‏ - Springer
We study ultraviolet cutoffs associated with the Weak Gravity Conjecture (WGC) and
Sublattice Weak Gravity Conjecture (sLWGC). There is a magnetic WGC cutoff at the energy …

Probing the universe through the stochastic gravitational wave background

S Kuroyanagi, T Chiba… - Journal of Cosmology and …, 2018‏ - iopscience.iop.org
Stochastic gravitational wave backgrounds, predicted in many models of the early universe
and also generated by various astrophysical processes, are a powerful probe of the …

LiteBIRD science goals and forecasts. A case study of the origin of primordial gravitational waves using large-scale CMB polarization

P Campeti, E Komatsu, C Baccigalupi… - … of Cosmology and …, 2024‏ - iopscience.iop.org
We study the possibility of using the LiteBIRD satellite B-mode survey to constrain models of
inflation producing specific features in CMB angular power spectra. We explore a particular …

Backreaction of axion-SU (2) dynamics during inflation

O Iarygina, EI Sfakianakis, R Sharma… - Journal of Cosmology …, 2024‏ - iopscience.iop.org
We consider the effects of backreaction on axion-SU (2) dynamics during inflation. We use
the linear evolution equations for the gauge field modes and compute their backreaction on …

Axion gauge field inflation and gravitational leptogenesis: A lower bound on modes from the matter-antimatter asymmetry of the Universe

RR Caldwell, C Devulder - Physical Review D, 2018‏ - APS
We present a toy model of an axion gauge field inflation scenario that yields viable density
and gravitational wave spectra. The scenario consists of an axionic inflaton in a steep …

Large tensor non-Gaussianity from axion-gauge field dynamics

A Agrawal, T Fujita, E Komatsu - Physical Review D, 2018‏ - APS
We show that an inflation model in which a spectator axion field is coupled to an SU (2)
gauge field produces a large three-point function (bispectrum) of primordial gravitational …

Chromo-natural inflation supported by enhanced friction from Horndeski gravity

T Murata, T Kobayashi - Journal of Cosmology and Astroparticle …, 2024‏ - iopscience.iop.org
We study the extension of the chromo-natural inflation model by incorporating nonminimal
coupling between the axion field and gravity. Nonminimal coupling is introduced so that it …

Gravitational axiverse spectroscopy: seeing the forest for the axions

E Dimastrogiovanni, M Fasiello, JM Leedom… - Journal of High Energy …, 2024‏ - Springer
A bstract We consider inflationary models with multiple spectator axions coupled to dark
gauge sectors via Chern-Simons (CS) terms. The energy injection into Abelian gauge fields …

Parity-violating scalar trispectrum from a rolling axion during inflation

T Fujita, T Murata, I Obata… - Journal of Cosmology and …, 2024‏ - iopscience.iop.org
We study a mechanism of generating the trispectrum (4-point correlation) of curvature
perturbation through the dynamics of a spectator axion field and U (1) gauge field during …