相关论文: Hidden Sector and Gravity
Assuming the validity of the general relativistic description of gravitation on astrophysical and cosmological length scales, we analytically infer that the Friedmann-Robertson-Walker cosmology with Einsteinian cosmological constant, and a…
Dark sectors with purely gravitational couplings to the Standard Model are unavoidably populated from the SM plasma by graviton exchange, and naturally provide DM candidates. We examine the production in the relativistic regime where the…
If the fundamental scale of gravity is of the order of 1 TeV, black holes might be produced at the Large Hadron Collider. This work presents simulations of black holes and other exotic models of physics beyond the Standard Model -…
We study a minimally extended version of the Standard Model where baryon number is gauged with a $U(1)_B$ symmetry. This model can be made anomaly-free by adding a set of additional fermions. The lightest component of these fermions behaves…
While observational cosmology has recently progressed fast, it revealed a serious dilemma called dark energy: an unknown source of exotic energy with negative pressure driving a current accelerating phase of the universe. All attempts so…
In these remarks, we clarify the problematic aspects of gravitational interaction in a weak-field limit of Kaluza-Klein models. We explain why some models meet the classical gravitational tests, while others do not. We show that variation…
A theory of gravity with torsion is examined in which the torsion tensor is constructed from the exterior derivative of an antisymmetric rank two potential plus the dual of the gradient of a scalar field. Field equations for the theory are…
The lack of detection of supersymmetric particles is leading to look at alternative avenues for explaining dark matter's effects. Among them, modified theories of gravity may play an important role accounting even for both dark components…
Scalar-tensor theories are promising dark energy models. A promising scalar-tensor theory, called Horndeski-like gravity, is coming from the application of the Horndeski gravity in string theory and cosmology that takes into account two…
We propose that anomalous gravitational effects currently attributed to dark matter can alternatively be explained as a manifestation of the inherent structure of space at galactic length scales. Specifically, we show that the inherent…
Scalar fields with inverse power-law effective potentials may provide a negative pressure component to the energy density of the universe today, as required by cosmological observations. In order to be cosmologically relevant today, the…
The physics of the dark sector has remained one of the controversial areas of modern cosmology at present and hence it naturally attracts massive attention to the scientific community. With the developments of the astronomical data, the…
We assume that the mass of the heavy standard particles ($Z,W,t,...$) arises from a special coupling with dark matter and that this implies a corresponding peculiar connection of these particles to the dark sector. We give examples of…
The linearized Einstein theory in the approximately flat time-space is modified accounting for a massive graviton as a dark matter in the universe. On the basis of magnetic-type Maxwell- Proca -Vlasov equations, the interactions of the…
We argue that the hidden sector potential energy is generically of order the intermediate scale although the true cosmological constant does vanish. This would significantly change the predicted values of soft parameters for a variety of…
In standard cosmologies, dark energy interacts only gravitationally with dark matter. There could be a non-gravitational interaction in the dark sector, leading to changes in the effective DE equation of state, in the redshift dependence of…
We investigate a beyond Standard Model (SM) featuring five new fields. Four fields encompassing three distinct spin states - scalar ($ S $), spinor ($ \psi^{1,2} $), and vector ($ V_{\mu} $) - together form the multi-component dark matter…
In the Regge-Teitelboim model, gravity is described by embedding the space-time manifold in a (usually flat) fixed higher-dimensional background, where the embedding coordinates, rather than the metric tensor, are the dynamical degrees of…
We consider an extension of the Standard Model within the frame work of Noncommutative Geometry. The model is based on an older model [St09] which extends the Standard Model by new fermions, a new U(1)-gauge group and, crucially, a new…
In this Letter, we motivate the fact that couplings between a scalar field and the Standard Model with strengths $10^{-6}(m_\phi/{\rm eV})^{-1/4}$ relative to gravity yield the total measured cosmological dark matter abundance over a broad…