Implications of Palatini gravity for inflation and beyond

ID Gialamas, A Karam, TD Pappas… - International Journal of …, 2023 - World Scientific
In this paper, we present an introduction to cosmic inflation in the framework of Palatini
gravity, which provides an intriguing alternative to the conventional metric formulation of …

Inflation in metric-affine quadratic gravity

ID Gialamas, K Tamvakis - Journal of Cosmology and …, 2023 - iopscience.iop.org
In the general framework of Metric-Affine theories of gravity, where the metric and the
connection are independent variables, we consider actions quadratic in the Ricci scalar …

Coupling metric-affine gravity to the standard model and dark matter fermions

C Rigouzzo, S Zell - Physical Review D, 2023 - APS
General relativity (GR) exists in different formulations, which are equivalent in pure gravity.
Once matter is included, however, observable predictions generically depend on the version …

Coupling metric-affine gravity to a Higgs-like scalar field

C Rigouzzo, S Zell - Physical Review D, 2022 - APS
General relativity (GR) exists in different formulations. They are equivalent in pure gravity but
generically lead to distinct predictions once matter is included. After a brief overview of …

Cosmological perturbation theory in metric-affine gravity

K Aoki, S Bahamonde, JG Valcarcel, MA Gorji - Physical Review D, 2024 - APS
We formulate cosmological perturbation theory around the spatially curved FLRW
background in the context of metric-affine gauge theory of gravity which includes torsion and …

Preheating in Einstein-Cartan Higgs Inflation: oscillon formation

M Piani, J Rubio - Journal of Cosmology and Astroparticle …, 2023 - iopscience.iop.org
We make use of classical lattice simulations in 3+ 1 dimensions to study the preheating
stage of Higgs Inflation in Einstein-Cartan gravity. Focusing for concreteness on a simplified …

Palatini R 2 quintessential inflation

K Dimopoulos, A Karam, SS López… - Journal of Cosmology …, 2022 - iopscience.iop.org
We construct a model of quintessential inflation in Palatini R 2 gravity employing a scalar
field with a simple exponential potential and coupled to gravity with a running non-minimal …

[HTML][HTML] Electroweak vacuum decay in metric-affine gravity

ID Gialamas, H Veermäe - Physics Letters B, 2023 - Elsevier
We investigate the stability of the electroweak vacuum in metric-affine gravity in which the
Standard Model Higgs boson can be non-minimally coupled to both the Ricci scalar and the …

Scale-invariant quadratic gravity and inflation in the Palatini formalism

ID Gialamas, A Karam, TD Pappas, VC Spanos - Physical Review D, 2021 - APS
In the framework of classical scale invariance, we consider quadratic gravity in the Palatini
formalism and investigate the inflationary predictions of the theory. Our model corresponds …

Reheating in models with non-minimal coupling in metric and Palatini formalisms

DY Cheong, SM Lee, SC Park - Journal of Cosmology and …, 2022 - iopscience.iop.org
We study reheating of inflationary models with general non-minimal coupling K (ϕ) R with K
(ϕ)∼√(V (ϕ)) where R is the Ricci scalar and R is the inflaton potential. In particular, when …