相关论文: Confusing dark matter particle properties with mod…
General Relativity (GR) exists in different formulations, which are equivalent in pure gravity. Once matter is included, however, observable predictions generically depend on the version of GR. In order to quantify the resulting ambiguity,…
Theoretical models of self-interacting dark matter represent a promising answer to a series of open problems within the so-called collisionless cold dark matter (CCDM) paradigm. In case of asymmetric dark matter, self-interactions might…
We consider f(R,T) modified theory of gravity, in which the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor of the matter, in order to investigate the dark-matter…
The cold dark matter model successfully explains both the emergence and evolution of cosmic structures on large scales and, when we include a cosmological constant, the properties of the homogeneous and isotropic Universe. However, the cold…
We explore a new horizon of modified gravity from the viewpoint of the particle physics. As a concrete example, we take the $F(R)$ gravity to raise a question: can a scalar particle ("scalaron") derived from the $F(R)$ gravity be a dark…
The logarithmic $R^2$-corrected $F(R)$ gravity is investigated as a prototype model of modified gravity theories with quantum corrections. By using the auxiliary field method, the model is described by the general relativity with a scalaron…
All $f(R)$ modified gravity theories are conformally identical to models of quintessence in which matter is coupled to dark energy with a strong coupling. This coupling induces a cosmological evolution radically different from standard…
We study the formation of large-scale structure in universes dominated by dark matter and driven to accelerated expansion by f(R) gravity in the Palatini formalism. If the dark matter is cold, practically all of these models are ruled out…
Dark matter (DM) with a mass below a few keV must have a phase space distribution that differs substantially from the Standard Model particle thermal phase space: otherwise, it will free stream out of cosmic structures as they form. We…
The cosmological evolution within the framework of exponential $F(R)$ gravity is analysed by assuming two forms for dark matter: (a) a standard dust-like fluid and (b) an axion scalar field. As shown in previous literature, an axion-like…
We investigate realistic models of compact objects, focusing on neutron and strange stars, composed by dense matter and dark energy in the form of a simple fluid or scalar field interacting with matter. For the dark energy component, we use…
We present for the first time the outcomes of a cosmological N-body simulation that simultaneously implements a Warm Dark Matter (WDM) particle candidate and a modified gravitational interaction in the form of $f(R)$ gravity, and compare…
Theoretical models of self-interacting dark matter offer a promising solution to several unresolved issues within the collisionless cold dark matter framework. For asymmetric dark matter, these self-interactions may encourage gravitational…
The fundamental nature of Dark Matter (DM) has not been established. Indeed, beyond its gravitational effects, DM remains undetected by present experiments. In this situation, it is reasonable to wonder if other alternatives can effectively…
All presently known stellar-dynamical constraints on the size and mass of the supermassive compact dark object at the Galactic center are consistent with a ball of self-gravitating, nearly non-interacting, degenerate fermions with mass…
Production of massive stable relics in $R^2$-modified gravity is considered. It is shown that the cosmological evolution and kinetics of massive species differs significantly from those in the conventional cosmology. The results are applied…
We propose a unified model for dark matter haloes and central galactic objects as a self-gravitating system of semidegenerated fermions in thermal equilibrium. We consider spherical symmetry and then we solve the equations of gravitational…
Gravitational positivity bounds provide consistency conditions for effective field theories with gravity. They turn out to be phenomenologically useful by providing lower bounds in parameters of new physics beyond the Standard Models (BSM).…
Universe heating in $R^2$-modified gravity is considered. The rates of particle production by the scalaron are calculated for different decay channels. Freezing of massive stable relics with the interaction strength typical for…
Over the past decades, General Relativity and the concordance $\Lambda$CDM model have been successfully tested using several different astrophysical and cosmological probes based on large datasets ({\it precision cosmology}). Despite their…