370 citations · 2.4k across the 38 of their papers we have counts for
17 papers · 1 filter
Breaking the axion abundance-isocurvature relation: Scale invariance and high-scale inflation
Mariaveronica De Angelis, Javier Rubio
A QCD axion accounting for dark matter through pre-inflationary misalignment is strongly constrained by CMB isocurvature bounds, which place the classic axion window in tension wit…
Preheating in Einstein-Cartan Higgs Inflation: Oscillon formation
Matteo Piani, Javier Rubio
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 simplif…
Cosmology and direct detection of the Dark Axion Portal
Juan Cortabitarte Gutiérrez, Bradley J. Kavanagh, Núria Castelló-Mor +4
The Dark Axion Portal provides a model for Dark Matter (DM) in which both Dark Photons and Axions can contribute to the present day abundance of DM. We study the par…
Hubble-induced phase transitions on the lattice with applications to Ricci reheating
Dario Bettoni, Asier Lopez-Eiguren, Javier Rubio
Using 3+1 classical lattice simulations, we follow the symmetry breaking pattern and subsequent non-linear evolution of a spectator field non-minimally coupled to gravity when the…
UV Freeze-in in Starobinsky Inflation
Nicolás Bernal, Javier Rubio, Hardi Veermäe
In the Starobinsky model of inflation, the observed dark matter abundance can be produced from the direct decay of the inflaton field only in a very narrow spectrum of close-to-con…
Boosting Ultraviolet Freeze-in in NO Models
Nicolás Bernal, Javier Rubio, Hardi Veermäe
We present a novel UV freeze-in mechanism for enhancing the dark matter abundance in cosmologies where inflation is followed by an epoch dominated by a fluid stiffer than radiation…
Preheating in Palatini Higgs inflation
Javier Rubio, Eemeli S. Tomberg
We study the details of preheating in Palatini Higgs inflation. We show, that contrary to what happens in the metric formulation of the model, the Universe does not reheat through…
Hidden Inflaton Dark Matter
Juan P. Beltrán Almeida, Nicolás Bernal, Javier Rubio +1
If cosmic inflation was driven by an electrically neutral scalar field stable on cosmological time scales, the field necessarily constitutes all or part of dark matter (DM). We stu…
Higgs inflation
Javier Rubio
The properties of the recently discovered Higgs boson together with the absence of new physics at collider experiments allows us to speculate about consistently extending the Stand…
On the geometrical interpretation of scale-invariant models of inflation
Georgios K. Karananas, Javier Rubio
We study the geometrical properties of scale-invariant two-field models of inflation. In particular, we show that when the field-derivative space in the Einstein frame is maximally…
Higgs inflation and vacuum stability
Javier Rubio
Inflation is nowadays a well-established paradigm consistent with all the observations. The precise nature of the inflaton is however unknown and its role could be played by any ca…
Living beyond the edge: Higgs inflation and vacuum metastability
Fedor Bezrukov, Javier Rubio, Mikhail Shaposhnikov
The measurements of the Higgs mass and top Yukawa coupling indicate that we live in a very special Universe, at the edge of the absolute stability of the electroweak vacuum. If ful…
Higgs-Dilaton cosmology: Universality vs. criticality
Javier Rubio, Mikhail Shaposhnikov
The Higgs-Dilaton model is able to produce an early inflationary expansion followed by a dark energy dominated era responsible for the late time acceleration of the Universe. At tr…
Higgs-Dilaton Cosmology: an effective field theory approach
Fedor Bezrukov, Georgios K. Karananas, Javier Rubio +1
The Higgs-Dilaton cosmological model is able to describe simultaneously an inflationary expansion in the early Universe and a dark energy dominated stage responsible for the presen…
Higgs-Dilaton cosmology: Are there extra relativistic species?
Juan Garcia-Bellido, Javier Rubio, Mikhail Shaposhnikov
Recent analyses of cosmological data suggest the presence of an extra relativistic component beyond the Standard Model content. The Higgs-Dilaton cosmological model predicts the ex…
Higgs-Dilaton Cosmology: From the Early to the Late Universe
Juan García-Bellido, Javier Rubio, Mikhail Shaposhnikov +1
We consider a minimal scale-invariant extension of the Standard Model of particle physics combined with Unimodular Gravity formulated in \cite{Shaposhnikov:2008xb}. This theory is…
Preheating in the Standard Model with the Higgs-Inflaton coupled to gravity
Juan Garcia-Bellido, Daniel G. Figueroa, Javier Rubio
We study the details of preheating in an inflationary scenario in which the Standard Model Higgs, strongly non-minimally coupled to gravity, plays the role of the inflaton. We find…