Related papers: Cannibal domination and the matter power spectrum
Many models of dark matter have been proposed in attempt to ease the $S_8$ tension between weak lensing and CMB experiments. One such exciting possibility is cannibalistic dark matter (CanDM), which has exothermal number-changing…
Interacting dark sectors may undergo changes in the number of their relativistic species during the early universe, due to a mass threshold $m$ (similar to changes in the Standard Model bath), and in doing so affect the cosmic history. When…
Very little is known about the cosmological history from after the end of inflation until Big Bang Nucleosynthesis. Various well-motivated models predict that the universe could have undergone a period of matter domination in this early…
We investigate a string-inspired dark energy scenario featuring a scalar field with a coupling to the Gauss-Bonnet invariant. Such coupling can trigger the onset of late dark energy domination after a scaling matter era. The universe may…
We calculate the early universe evolution of perturbations in the dark matter energy density in the context of simple dark sector models containing a GeV scale light mediator. We consider the case that the mediator is long lived, with…
Thermal freeze-out or freeze-in during a period of early matter domination can give rise to the correct dark matter abundance for $\langle \sigma_{\rm ann} v \rangle_{\rm f} < 3 \times 10^{-26}$ cm$^3$ s$^{-1}$. In the standard scenario, a…
It is commonly assumed that the energy density of the Universe was dominated by radiation between reheating after inflation and the onset of matter domination 54,000 years later. While the abundance of light elements indicates that the…
We consider the interaction between dark matter and dark energy in the framework of holographic dark energy, and propose a natural and physically plausible form of interaction, in which the interacting term is proportional to the product of…
Recently, attempts have been made to understand the apparent near coincidence of the present dark energy and matter energy in terms of a dynamical attractor-like solution for the evolution of a scalar field. In these models the field…
We present a new scenario for the development of the Universe after the Big Bang, built on the conjecture that a vast majority of the primordial quark matter did not undergo a phase transition to normal nuclear matter, but rather split up…
Dark energy and dark matter are the dominant sources in the evolution of the late universe. They are currently only indirectly detected via their gravitational effects, and there could be a coupling between them without violating…
We investigate the influence of an early matter-dominated era in cosmic history on the dynamics of cosmic strings and the resulting stochastic gravitational waves. Specifically, we examine the case where this era originates from the dark…
We analyzed available observational data of a sample of dark matter (DM) dominated galaxies and clusters of galaxies and we have found correlations between the virial mass, $M_{vir}$, of halos and basic parameters of their cores, namely,…
We consider the generic scenario of dark energy which arises through the latent heat of a hidden sector first order cosmological phase transition. This field could account for the extra radiation degree of freedom suggested by the CMB. We…
We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has…
Recent observations of the cosmic microwave background (CMB) anisotropies and the distribution of galaxies, galaxy clusters, and the Lyman Alpha forest have constrained the shape of the power spectrum of matter fluctuations on large scales…
We consider the implications of a scalar field interacting with the dark matter fluid on the energy spectrum of the primordial gravitational waves. We choose an interaction type which before a critical matter density $\rho_m^c$ during the…
We investigate the impact on the classical dynamics of dark matter particles and dark energy of a non-minimal coupling in the dark sector, assuming that the mass of the dark matter particles is coupled to a dark energy scalar field. We show…
If dark energy and dark matter interact via exchange of energy and momentum, then this may affect the galaxy power spectrum on large scales. When this happens, it may be degenerate with the signal from primordial non-Gaussianity via…
The Hot Big Bang is often considered as the origin of all matter and radiation in the Universe. Primordial nucleosynthesis (BBN) provides strong evidence that the early Universe contained a hot plasma of photons and baryons with a…