Related papers: Fifth force induced by a chameleon field on nested…
In this article we discuss some aspects of solar physics from the standpoint of the so-called chameleon fields (i.e. quantum fields, typically scalar, where the mass is an increasing function of the matter density of the environment).…
Massive gravity, galileon and braneworld models that modify gravity to explain cosmic acceleration utilize the nonlinear field interactions of the Vainshtein mechanism to screen fifth forces in high density regimes. These source-dependent…
Chameleon scalar field is a new model, which introduced to provide a mechanism for exhibiting accelerating universe. Chameleon field has several interesting aspects, such as field dependence on the local matter density. For this model we…
The symmetron is a typical example of screened modified gravity, wherein the symmetron force is dynamically suppressed in dense environments. This allows it to hide in traditional tests of gravity. However, the past decade has seen great…
Aims. We investigate the gravitational redshift in clusters of galaxies in the symmetron and Hu-Sawicky $f(R)$ models. The characteristic feature of both models is the screening mechanism that hides the fifth force in dense environments…
The consideration is presented of possible neutron Lloyd's mirror interferometer experiment to search for strongly coupled chameleon fields. The chameleon scalar fields were proposed to explain the early and late time acceleration of…
We present a framework for embedding scalar-tensor models of screened modifed gravity such as chameleons, symmetrons and environmental dilatons into global supersymmetry. This achieved by secluding the dark sector from both the observable…
The late-time accelerated expansion of the universe could be caused by a scalar field that is screened on small scales, as in chameleon or symmetron scenarios. We present an analogy between thin shell configurations of such scalar fields…
Scalar self interactions are known to weaken considerably the current constraints on scalar-mediated fifth forces. We consider a scalar field with a quartic self interaction and gravitation-strength Yukawa couplings to matter particles.…
Cross-correlating two different types of galaxy gives rise to parity breaking in the correlation function that derives from differences in the galaxies' properties and environments. This is typically associated with a difference in galaxy…
Scalar-tensor theories are studied in the context of cosmological evolution, where the expansion history of the Universe is reconstructed. It is considered quintessence/phantom models, where inflation and cosmic acceleration are reproduced.…
The best laboratory constraints on strongly coupled chameleon fields come not from tests of gravity per se but from precision measurements of the Casimir force. The chameleonic force between two nearby bodies is more akin to a Casimir-like…
If the recent observations suggesting a time variation of the fine structure constant are correct, they imply the existence of an ultra light scalar particle. This particle inevitably couples to nucleons through the \alpha-dependence of…
We discuss the scalar mode of gravitational waves emerging in the context of $F(R)$ gravity by taking into account the chameleon mechanism. Assuming a toy model with a specific matter distribution to reproduce the environment of detection…
We use two new hydrodynamical simulations of $\Lambda$CDM and $f(R)$ gravity to test the methodology used by Wilcox et al. 2015 (W15) in constraining the effects of a fifth force on the profiles of clusters of galaxies. We construct…
A matter-coupled scalar field model is presented in obtaining a scalar fifth force when the constraint of the current cosmological constant is satisfied. The interaction potential energy density between the scalar field and matter has a…
Chameleon gravity is a scalar-tensor theory that includes a non-minimal coupling between the scalar field and the matter fields and yet mimics general relativity in the Solar System. The scalar degree of freedom is hidden in high-density…
We offer predictions of symmetron modified gravity in the neighborhood of realistic dark matter halos. The predictions for the fifth force are obtained by solving the nonlinear symmetron equation of motion in the spherical NFW…
The MICROSCOPE experiment was designed to test the weak equivalence principle in space, by comparing the low-frequency dynamics of cylindrical "free-falling" test masses controlled by electrostatic forces. We use data taken during technical…
A coupling between a scalar field (representing the dark energy) and dark matter could produce rich phenomena in cosmology. It affects cosmic structure formation mainly through the fifth force, a velocity-dependent force that acts parallel…