Related papers: MICROSCOPE limits for new long-range forces and im…
The hypothetical massive dark photon ($\gamma'$) which has kinetic mixing with the SM photon can decay electromagnetically to $e^+e^-$ pairs if its mass $m$ exceeds $2m_e$ and otherwise into three SM photons. These decays yield cosmological…
Dark sectors lying beyond the Standard Model and containing sub-GeV particles which are bilinearly coupled to nucleons would induce quantum forces of the Casimir-Polder type in ordinary matter. Such new forces can be tested by a variety of…
We consider a fifth force to be an interaction that couples to matter with a strength that grows with the number of atoms. In addition to competing with the strength of gravity a fifth force can give rise to violations of the equivalence…
Consistency relations involving the soft limit of the (n + 1)-correlator functions of dark matter and galaxy overdensities can be obtained, both in real and redshift space, thanks to the symmetries enjoyed by the Newtonian equations of…
Limits on spin-0 axion-like-particles (ALPs) coupling to photons are reinterpreted as constraints on massive spin-2 graviton-like-particles (GLPs) with universal coupling $\alpha_\text{G}/M_\text{P}$ (where $M_\text{P}$ is the reduced…
New dark vector bosons that couple very feebly to regular matter can be created in the early universe and decay after the onset of big bang nucleosynthesis (BBN) or the formation of the cosmic microwave background (CMB) at recombination.…
Massless neutrinos will mix if their couplings to gravity are flavor dependent, i.e., violate the principle of equivalence. Because the gravitational interaction grows with neutrino energy, the solar neutrino problem and the recent…
A model of dark energy and dark matter was proposed earlier by one of us (PQH) which involved an unbroken gauge group $SU(2)_Z$ whose coupling $\alpha_Z \equiv g_Z^2/4 \pi\sim O(1)$ at a scale $\Lambda_Z \sim 3 \times 10^{-3} eV$ starting…
In a class of supersymmetric grand unified theories, including those based on the gauge group $SO(10)$, there are new contributions to the electric dipole moments of the neutron and electron, which arise as a heavy top quark effect. These…
We show that in the Higgs model leading to a slightly massive photon there are one-loop diagrams which induce equivalence principle violations. This and other considerations implicate rather stringent constraints in the parameter space of…
The $^1S_0$ pairing in neutron matter has been investigated in presence of realistic two-- and three--nucleon interactions. We have adopted the Argonne $v_{8^\prime}$ NN and the Urbana IX 3N potentials. Quantum Monte Carlo theory,…
The basic idea that gravity can be a long-wavelength effect {\it induced} by the peculiar ground state of an underlying quantum field theory leads to consider the implications of spontaneous symmetry breaking through an elementary scalar…
Using a data set of 2.93 fb$^{-1}$ taken at a center-of-mass energy $\sqrt{s}$ = 3.773 GeV with the BESIII detector at the BEPCII collider, we perform a search for an extra U(1) gauge boson, also denoted as a dark photon. We examine the…
The spontaneous breaking of U(1)_B-L around the scale of grand unification can simultaneously account for hybrid inflation, leptogenesis, and neutralino dark matter, thus resolving three major puzzles of particle physics and cosmology in a…
Restrictions imposed by gauge invariance in noncommutative spaces together with the effects of ultraviolet/infrared mixing lead to strong constraints on possible candidates for a noncommutative extension of the Standard Model. We study a…
New gauge bosons at the MeV scale with tiny gauge couplings (so-called dark photons) can be responsible for the freeze-in production of dark matter and provide a clear target for present and future experiments. We study the effects of…
We consider a gauged $U(1)_{L_\mu-L_\tau}$ extension of the left-right symmetric theory in order to simultaneously explain neutrino mass, mixing and the muon anomalous magnetic moment. We get sizeable contribution from the interaction of…
Dark energy in General Relativity is typically non-interacting with other matter. However, it is possible that the dark energy interacts with the dark matter, and in this case, the dark matter can violate the universality of free fall (the…
The possibility of new short-distance physics applicable inside the cores of NS is incorporated into the equation of state generated by the quark-meson coupling model. The contribution of this new physics to the energy density is taken to…
Direct searches of dark matter are performed at accelerator facilities. The existence of a new vector boson has been postulated in different scenarios where in the most basic scheme the coupling to the SM can be achieved via a kinetic…