Related papers: Chameleon Screening in Cosmic Voids
Chameleon scalar fields can screen their associated fifth forces from detection by changing their mass with the local density. These models are an archetypal example of a screening mechanism, and have become an important target for both…
A light scalar field framework of dark energy, sometimes referred to as quintessence, introduces a fifth force between normal matter objects. Screening mechanisms, such as the chameleon model, allow the scalar field to be almost massless on…
The chameleon is a theorised scalar field that couples to matter and possess a screening mechanism, which weakens observational constraints from experiments performed in regions of higher matter density. One consequence of this screening…
We study the impact of cosmological scale modifications to General Relativity on the dynamics of halos within voids by comparing N-body simulations incorporating Hu-Sawicki $f(R)$ gravity, with $|f_{R0}|=10^{-6}$ and $10^{-5}$, to those of…
We investigate the validity of screening mechanism of the fifth force for chameleon field in highly inhomogeneous density profile. For simplicity, we consider a static and spherically symmetric system which is composed of concentric…
We investigate the behavior of the fifth force in voids in chameleon models using the spherical collapse method. Contrary to Newtonian gravity, we find the fifth force is repulsive in voids. The strength of the fifth force depends on the…
Chameleon and symmetron theories serve as archetypal models for how light scalar fields can couple to matter with gravitational strength or greater, yet evade the stringent constraints from classical tests of gravity on Earth and in the…
The chameleon model is a scalar field theory with a screening mechanism that explains how a cosmologically relevant light scalar can avoid the constraints of intra-solar-system searches for fifth-forces. The chameleon is a popular dark…
If dark energy --- which drives the accelerated expansion of the universe --- consists of a light scalar field, it might be detectable as a "fifth force" between normal-matter objects, in potential conflict with precision tests of gravity.…
Chameleon gravity is an example of a model that gives rise to interesting phenomenology on cosmological scales while simultaneously possessing a screening mechanism, allowing it to avoid solar system constraints. Such models result in…
The chameleon mechanism enables a long range fifth force to be screened in dense environments when non-trivial self interactions of the field cause its mass to increase with the local density. To date, chameleon fifth forces have mainly…
The chameleon gravity model postulates the existence of a scalar field that couples with matter to mediate a fifth force. If it exists, this fifth force would influence the hot X-ray emitting gas filling the potential wells of galaxy…
We review the tantalising prospect that the first evidence for the dark energy driving the observed acceleration of the Universe on giga-parsec scales may be found through metre scale laboratory based atom interferometry experiments. To do…
Theories that attempt to explain cosmic acceleration by modifying gravity typically introduces a long-range scalar force that needs to be screened on small scales. One common screening mechanism is the chameleon, where the scalar force is…
Chameleons are light scalar fields with remarkable properties. Through the interplay of self-interactions and coupling to matter, chameleon particles have a mass that depends on the ambient matter density. The manifestation of the fifth…
In this paper, we study the distribution of dark matter halos and voids using high resolution simulations in f(R) gravity models with the chameleon mechanism to screen the fifth force in dense environment. For dark matter halos, we show…
Scalar-tensor theories with screening mechanisms come with non-linearities that make it difficult to study setups of complex geometry without resorting to numerical simulations. In this article, we use the $\textit{femtoscope}$ code that we…
Screened modified gravity predicts potentially large signatures in the peculiar velocity field that makes it an interesting probe to test gravity on cosmological scales. We investigate the signatures induced by the Symmetron and a Chameleon…
Many non-linear scalar field theories possess a screening mechanism that can suppress any associated fifth force in dense environments. As a result, these theories can evade local experimental tests of new forces. Chameleon-like screening,…
Observational evidence implying the accelerated expansion of the universe has been the motivation to develop various classes of modified gravity theories. One of them uses the so-called "screening mechanism", which is successful in…