Related papers: Cosmological Constraints on Dark Neutrino Towers
Neutrino masses and quantum gravity are strong reasons to extend the standard model of particle physics. A large extra dimension can be motivated by quantum gravity and can explain the small neutrino masses with new singlet states that…
It was recently understood that if the swampland conjectures are confronted to experiment they naturally point to a solution of the cosmological hierarchy problem in which the smallness of the dark energy is ascribed to an internal (dark)…
We study the consequences of the gravitino decay into dark matter. We suppose that the lightest neutralino is the main component of dark matter. In our framework gravitino is heavy enough to decay before Big Bang Nucleosynthesis starts. We…
We study the landscape of lower-dimensional vacua of the SM coupled to gravity in the presence of the ``dark dimension'' of size $R_\perp$ in the micron range, focusing on the validity of the swampland conjecture forbidding the presence of…
We study the consequences of the gravitino decay into dark matter. We suppose that the lightest neutralino is the main component of dark matter. In our framework gravitino is heavy enough to decay before Big Bang Nucleosynthesis starts. We…
In models of universal extra dimensions, gravity and all standard model fields propagate in the extra dimensions. Previous studies of such models have concentrated on the Kaluza-Klein (KK) partners of standard model particles. Here we…
We explore the potential implications of Kaluza-Klein (KK) gravity in unifying the dark sector of the Universe. Through dimensional reduction in KK gravity, the 5D spacetime framework can be reformulated in terms of a 4D spacetime metric,…
We discuss the phenomenological consequences of theories which describe sterile neutrinos in large extra dimensions. We show that the Kaluza-Klein tower of the singlet neutrinos, albeit tiny individual contribution in electroweak processes,…
We consider a toroidal extra-dimensional space with shape moduli $\theta$ which is the angle between the two large extra dimensions $R_1$ and $R_2$ (twisted LED with $\delta=2$). The Kaluza-Klein (KK) compactification results in a tower of…
In the dark dimension scenario, which predicts an extra dimension of micron scale, dark gravitons (KK modes) are a natural dark matter candidate. In this paper, we study observable features of this model. In particular, their decay to…
Models of Universal Extra Dimensions (UED) at the TeV scale lead to the presence of Kaluza Klein (KK) excitations of the ordinary fermions and bosons of the Standard Model that may be observed at hadron and lepton colliders. A conserved…
The cold dark matter may be in a meta-stable state and decays to other particles with a very long lifetime. If the decaying products of the dark matter are weakly interacting, e.g. neutrinos, then it would have little impact on…
We discuss the phenomenological consequences of theories which describe sterile neutrinos in large extra dimensions, in the so-called bulk. We briefly outline how the cumulative non-decoupling effect due to the tower of Kaluza-Klein singlet…
We explore the cosmology of the Dark Dimension scenario taking into account perturbations in the linear regime. In the context of the Dark Dimension scenario, a natural candidate for dark matter in our universe is the excitations of a tower…
We propose a unified framework based on sterile neutrinos propagating in large extra dimensions (LED) and coupled to a pseudo-Nambu-Goldstone boson (Majoron) arising from spontaneous lepton number violation. In this setup, the lightest…
In models with universal extra dimensions (i.e. in which all Standard Model fields, including fermions, propagate into compact extra dimensions) momentum conservation in the extra dimensions leads to the conservation of Kaluza--Klein (KK)…
We present a comprehensive analysis of constraints on the sterile neutrino as a dark matter candidate. The minimal production scenario with a standard thermal history and negligible cosmological lepton number is in conflict with…
In this paper, we propose a new framework for dark-matter physics. Rather than focus on one or more stable dark-matter particles, we instead consider a multi-component framework in which the dark matter of the universe comprises a vast…
The generation of dark matter in late decays of quasi-stable massive particles has been proposed as a viable framework to address the excess of power found in numerical N-body simulations for cold dark matter cosmologies. We identify a…
Cosmological measurements are affected by the energy density of both active and sterile massive neutrinos. We extend here a recent analysis of current cosmological data to non minimal cosmologies. Several possible scenarios are examined: a…