Related papers: Minimal targets for dilaton direct detection
Ultra-light scalar fields may explain the nature of the dark matter in our universe. If such scalars couple quadratically to particles of the Standard Model the scalar acquires an effective mass which depends on the local matter energy…
We consider a late closed universe of which scale factor is a power function of time using observational data from combined WMAP5+BAO+SNIa dataset and WMAP5 dataset. The WMAP5 data give power-law exponent, $\alpha = 1.01$ agreeing with the…
We extend the Standard Model (SM) by introducing a $U(1)'$ gauge boson and a real pseudo-scalar field, both odd under a $\mathbb{Z}_2$ symmetry. The resulting low-energy spectrum consists of a stable vector as the dark matter candidate, and…
We analyse the role, on large cosmological scales and laboratory experiments, of the leading curvature squared contributions to the low energy effective action of gravity. We argue for a natural relationship $c_0\lambda^2\simeq 1$ at…
Dark matter self-interactions have important implications for the distributions of dark matter in the Universe, from dwarf galaxies to galaxy clusters. We present benchmark models that illustrate characteristic features of dark matter that…
We study a Dirac Dark Matter particle interacting with ordinary matter via the exchange of a light pseudo-scalar, and analyze its impact on both direct and indirect detection experiments. We show that this candidate can accommodate the…
In the framework of teleparallel equivalent of general relativity, we study a gravity theory where a scalar field beyond its minimal coupling, is also coupled with the vector torsion through a non-minimal derivative coupling. After a…
We discuss cosmological constraints on a dark scalar particle mixing with the Standard Model Higgs boson. We pay particular attention to the dark scalar production process when the reheating temperature of the Universe is very low, which…
We present a detailed study of dark matter phenomenology in low-scale left-right symmetric models. Stability of new fermion or scalar multiplets is ensured by an accidental matter parity that survives the spontaneous symmetry breaking of…
Spin-dependent fifth-forces are associated with particles beyond the standard model. In particular, light pseudo-scalar bosons mediate long-range forces, allowing mass to interact with spins. The search of these interactions can be…
We consider scalar field models of dark energy interacting with dark matter through a coupling proportional to the contraction of the four-derivative of the scalar field with the four-velocity of the dark matter fluid. The coupling is…
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…
Numerical simulations show that a long-range scalar interaction in a single species of massive dark matter particles causes voids between the concentrations of large galaxies to be more nearly empty, suppresses accretion of intergalactic…
We reinterpret the results of the direct searches for dark matter in terms of milli-interacting dark particles. The model reproduces the positive results from DAMA/LIBRA and CoGeNT and is consistent with the absence of signal in the…
Theories of dark energy require a screening mechanism to explain why the associated scalar fields do not mediate observable long range fifth forces. The archetype of this is the chameleon field. Here we show that individual atoms are too…
We study the cosmological evolution and phenomenological properties of scalar bosons in the keV to MeV range that have a tiny mixing with the Standard Model Higgs boson. The mixing determines both the abundance of light scalars produced via…
The observed accelerating universe indicates the presence of Dark Energy which is probably interpreted in terms of an extremely light gravitational scalar field. We suggest a way to probe this scalar field which contributes to optical…
A new technique to search for new scalar and tensor interactions at the sub-micrometer scale is presented. The technique relies on small shifts of nuclear gamma lines produced by the coupling between matter and the nuclei in the source or…
We investigate scalar-tensor theories where matter couples to the scalar field via a kinetically dependent conformal coupling. These models can be seen as the low-energy description of invariant field theories under a global Abelian…
Thermal freeze-out is a prominent example of dark matter (DM) production mechanism in the early Universe that can yield the correct relic density of stable weakly interacting massive particles (WIMPs). At the other end of the mass scale,…