相关论文: Jump Starting the Dark Sector with a Phase Transit…
If the dark matter is part of a hidden sector with only very feeble couplings to the Standard Model, the lightest particle in the hidden sector will generically be long-lived and could come to dominate the energy density of the universe…
Portal Matter, with both SM and dark charges, induces KM between the $U(1)_D$ dark photon and the SM gauge fields offering an attractive mechanism by which light thermal DM can obtain its observed relic density. If DM is fermionic, the CMB…
In this talk I present a new model of a unified dark sector, where late-time cosmic acceleration emerges from the dark matter (DM) superfluid framework. We will start by reviewing the dark matter superfluid model and show how it describes…
We consider theories where dark matter is composed of a thermal relic of weak scale mass, whose couplings to the Standard Model (SM) are however too small to give rise to the observed abundance. Instead, the abundance is set by annihilation…
We point out that if the sector associated with the Standard Model degrees of freedom entered an open string Hagedorn phase in the early universe while the dark radiation sector was not part of this plasma, then this can lead to low values…
We consider a non-Abelian dark SU(2)$_{\rm D}$ model where the dark sector couples to the Standard Model (SM) through a Higgs portal. We investigate two different scenarios of the dark sector scalars with $Z_2$ symmetry, with Higgs portal…
The accumulated energy density of the excited entropy modes in multiple field inflationary scenarios can play the role of dark matter. In the usual case of a flat field space without any turning trajectory, only light superhorizon entropy…
Cosmological first order phase transitions are typically associated with physics beyond the Standard Model, and thus of great theoretical and observational interest. Models of phase transitions where the energy is mostly converted to dark…
We investigate generalized interacting dark matter-dark energy scenarios with a time-dependent coupling parameter, allowing also for freedom in the neutrino sector. The models are tested in the phantom and quintessence regimes,…
We construct modified cosmological scenarios through the application of the first law of thermodynamics in the universe horizon, but using the generalized, nonextensive Tsallis entropy instead of the usual Bekenstein-Hawking one. We result…
In the minimal supersymmetric standard model (MSSM) extended by a singlet superfield, when the coupling between the singlet sector and the MSSM sector is tiny, the singlet sector can be a quasi dark sector with supersymmetry (SUSY). We…
Atomic dark matter is a simple but highly theoretically motivated possibility for an interacting dark sector that could constitute some or all of dark matter. We perform a comprehensive study of precision cosmological observables on minimal…
In this work we study a scale invariant gravity theory containing two scalar fields, dust particles and a measure defined from degrees of freedom independent of the metric. The integration of the degrees of freedom that define the measure…
We consider a generic first-order phase transition at finite temperature and investigate to what extent a population of primordial black holes, of variable masses, can affect the rate of bubble nucleation. Using a thin-wall approximation,…
A compelling way to address the inflationary period is via the warm inflation scenario, where the interaction of the inflaton field with other degrees of freedom affects its dynamics in such a way that slow-roll inflation is maintained by…
Kinematically forbidden channels can set the freeze-out dark matter (DM) relic abundance. These channels are described by DM annihilations into heavier states, which vanish at zero temperature limit, but occur at finite temperatures in the…
We consider dark matter models in which the mass splitting between the dark matter particles and their annihilation products is tiny. Compared to the previously proposed Forbidden Dark Matter scenario, the mass splittings we consider are…
The framed standard model (FSM), constructed to explain the empirical mass and mixing patterns of quarks and leptons, gives the same result as the standard model in almost all areas in particle physics where it has been successfully…
It is found that the evolutions of density perturbations on the super-Hubble scales are unstable in the model with dark-sector interaction $Q$ proportional to the energy density of cold dark matter (CDM) $\rho_m$ and constant equation of…
We revisit the non-thermal dark matter (DM) production during the thermalization and reheating era after inflation. The decay of inflaton produces high-energy particles that are thermalized to complete the reheating of the Universe. Before…