47 citations · 140 across the 19 of their papers we have counts for
23 papers
All Quiet on the Vector Front: Scalar Growth and Perturbative Control in Horndeski--Weyl-squared Gravity
Antonio De Felice, Guillem Domènech, Jan Tränkle
Higher-order curvature corrections to general relativity arise naturally in many fundamental theories and provide phenomenologically interesting low-energy effective field theories…
Unpolarized Low-Frequency Tail of Causal Chiral Gravitational Waves
Tikinas Chabour, Guillem Domènech, Alexander Ganz +1
Parity violation in the early Universe may lead to a chiral gravitational wave background. We show that, for finite-time parity-violating sources, the low-frequency tail of the gen…
The cosmology of long range Yukawa interactions in general backgrounds
Guillem Dom`enech, Panagiotis Giannadakis
Long-range forces in the early universe may lead to early structure formation and, perhaps, to primordial black holes. We generalise previous studies of fermions coupled to a light…
Gravitational wave constraints on the Paneitz operator
Robin Valtin, Alexander Ganz, Guillem Domènech
The Paneitz operator is a dimension-4 conformally invariant fourth-order differential operator that has recently attracted attention for possible cancellations of the vacuum energy…
Observable Gravitational Wave Strain at Second Order
Guillem Domènech, Shi Pi, Ao Wang
There is currently no rigorous definition of gravitational wave strain at second order in cosmological perturbation theory. The usual association of gravitational waves with transv…
On the adiabatic initial conditions for a particle gas in cosmology
Guillem Domènech
In view of recent interest in the role of "dark" radiation in cosmology, such as cosmic gravitational waves, sterile neutrinos, and dark photons, we clarify the definition of adiab…
Apparent Lorentz violation from disformally coupled ultralight dark matter
Guillem Domènech, Apostolos Tsabodimos, Apostolos Tsampodimos +3
We study the impact of general disformal metric transformations on fermions, which shift the gravitational metric by an additional rank-2 tensor. This tensor can in principle be co…
On the consistent disformal couplings to fermions
Guillem Domènech, Alexander Ganz, Apostolos Tsabodimos +1
Disformal couplings to fermions lead to a unique derivative coupling to the axial fermionic current, which contains higher derivatives in general. We derive general conditions on c…
Unique gravitational wave signatures of GLPV scalar-tensor theories
Guillem Domènech, Alexander Ganz, Mohammad Ali Gorji +1
We study gravitational waves induced by scalar primordial fluctuations in Gleyzes-Langlois-Piazza-Vernizzi (GLPV), beyond Horndeski, scalar-tensor theories. We uncover, at the leve…
Gravitational waves induced by matter isocurvature in general cosmologies
Guillem Domènech, Jan Tränkle
The expansion history and content of the Universe between the end of inflation and the onset of Big Bang Nucleosynthesis is mostly unknown. In this paper, we study gravitational wa…
Induced Gravitational Waves as Cosmic Tracers of Leptogenesis
Marco Chianese, Guillem Domènech, Theodoros Papanikolaou +2
We demonstrate that induced gravitational waves (IGWs) can naturally emerge within well-motivated realizations of thermal leptogenesis, thereby providing a possible observational h…
Regularizing the induced GW spectrum with dissipative effects
Guillem Domènech, Jens Chluba
Finite mean free paths of light particles, like photons and neutrinos, lead to dissipative effects and damping of small-scale density fluctuations in the early universe. We study t…
Connecting Relativistic MOND Theories with Mimetic Gravity
Guillem Domènech, Alexander Ganz
We find a connection between relativistic Modified Newtonian Dynamics (MOND) theories and (scalar) mimetic gravity. We first demonstrate that any relativistic MOND model featuring…
From formation to evaporation: Induced gravitational wave probes of the primordial black hole reheating scenario
Guillem Domènech, Jan Tränkle
We study the Primordial Black Hole (PBH) reheating scenario, where PBHs originate in a general cosmological background. In this scenario, ultralight PBHs with masses $M\lesssim 10^…
Finite distance effects on the Hellings-Downs curve in modified gravity
Guillem Domènech, Apostolos Tsabodimos, Apostolos Tsampodimos
There is growing interest in the overlap reduction function in pulsar timing array observations as a probe of modified gravity. However, current approximations to the Hellings-Down…
Enhanced induced gravitational waves in Horndeski gravity
Guillem Domènech, Alexander Ganz
We study secondary gravitational wave production in Horndenski gravity, when the scalar field dominates the very early universe. We find that higher derivative interactions easily…
Induced Gravitational Wave interpretation of PTA data: a complete study for general equation of state
Guillem Domènech, Shi Pi, Ao Wang +1
We thoroughly study the induced gravitational wave interpretation of the possible gravitational wave background reported by PTA collaborations, considering the unknown equation of…
Probing modified Hawking evaporation with gravitational waves from the primordial black hole dominated universe
Shyam Balaji, Guillem Domènech, Gabriele Franciolini +2
It has been recently proposed that Hawking evaporation might slow down after a black hole has lost about half of its mass. Such an effect, called "memory burden", is parameterized…
GW Backgrounds associated with PBHs
Guillem Domènech
PBH formation requires high-density regions in the (random) density field filling the primordial universe. While only the largest (and so rarest) overdensities collapse to form PBH…
Probing Primordial Black Hole Scenarios with Terrestrial Gravitational Wave Detectors
Guillem Domènech, Misao Sasaki
It is possible that primordial black holes consitute (or consituted) a significant fraction of the energy budget of our universe. Terrestrial gravitational wave detectors offer the…
Cosmological Gravitational Waves from Isocurvature Fluctuations
Guillem Domènech
Gravitational waves induced by large primordial curvature fluctuations may result in a sizable stochastic gravitational wave background. Interestingly, curvature fluctuations are g…
Parametric resonance of gravitational waves in general scalar-tensor theories
Yi-Fu Cai, Guillem Domènech, Alexander Ganz +3
Gravitational waves offer a potent mean to test the underlying theory of gravity. In general theories of gravity, such as scalar-tensor theories, one expects modifications in the f…
An exact model for enhancing/suppressing primordial fluctuations
Guillem Domènech, Gerson Vargas, Teófilo Vargas
Enhancements of primordial curvature fluctuations in single field inflation often involve departures from attractor trajectories in the phase space. We study enhancement/suppressio…