Galileon models must obey a void-depth limit tied to expansion history to avoid force breakdowns, excluding ~60% of a linear parameterization's space by z less than or equal to 10.
The Vainshtein mechanism beyond the quasi-static approximation
3 Pith papers cite this work. Polarity classification is still indexing.
3
Pith papers citing it
abstract
Theories of modified gravity, in both the linear and fully non-linear regime, are often studied under the assumption that the evolution of the new (often scalar) degree of freedom present in the theory is quasi-static. This approximation significantly simplifies the study of the theory, and one often has good reason to believe that it should hold. Nevertheless it is a crucial assumption that should be explicitly checked whenever possible. In this paper we do so for the Vainshtein mechanism. By solving for the full spatial and time evolution of the Dvali-Gabadadze-Porrati and the Cubic Galileon model, in a spherical symmetric spacetime, we are able to demonstrate that the Vainshtein solution is a stable attractor and forms no matter what initial conditions we take for the scalar field. Furthermore,the quasi-static approximation is also found to be a very good approximation whenever it exists. For the best-fit Cubic Galileon model, however, we find that for deep voids at late times, the numerical solution blows up at the same time as the quasi-static solution ceases to exist. We argue that this phenomenon is a true instability of the model.
citation-role summary
background 1
citation-polarity summary
years
2026 3verdicts
UNVERDICTED 3roles
background 1polarities
background 1representative citing papers
A master screening equation is derived for luminal Horndeski gravity that recovers Vainshtein and Chameleon mechanisms and introduces Phaedrus screening with screening radius scaling linearly with source mass.
ACG models embed the observationally preferred phantom-crossing dark energy behavior inside a consistent Horndeski Lagrangian and achieve data fits of similar quality to w0waCDM while being narrowed by perturbative probes.
citing papers explorer
-
How deep can a cosmic void be? Voids-informed theoretical bounds in Galileon gravity
Galileon models must obey a void-depth limit tied to expansion history to avoid force breakdowns, excluding ~60% of a linear parameterization's space by z less than or equal to 10.
-
A Master Equation for Screening in Luminal Horndeski Gravity
A master screening equation is derived for luminal Horndeski gravity that recovers Vainshtein and Chameleon mechanisms and introduces Phaedrus screening with screening radius scaling linearly with source mass.
-
Constraints on Horndeski Gravity with Phantom Crossing
ACG models embed the observationally preferred phantom-crossing dark energy behavior inside a consistent Horndeski Lagrangian and achieve data fits of similar quality to w0waCDM while being narrowed by perturbative probes.