Related papers: Dark Strings
If the hidden sector contains more than one U(1) groups, additional dim-4 couplings (beyond the kinetic mixing) between the massive U(1) fields and the hypercharge generally appear. These are of the form similar to the Chern-Simons…
Persisting tensions between high-redshift and low-redshift cosmological observations suggest the dark energy sector of the Universe might be more complex than the positive cosmological constant of the $\Lambda$CDM model. Motivated by string…
This work discusses a few theories including the interaction of dark matter, cosmic strings, and locally coupled dark energy. The paper also examines mathematical models used to describe the pressure and density within a star, including the…
Dark matter (DM) charged under a dark U(1) force appears in many extensions of the Standard Model, and has been invoked to explain anomalies in cosmic-ray data, as well as a self-interacting DM candidate. In this paper, we perform a…
In this thesis, we discuss theoretical properties of various Higgs sectors, and we analyze constraints from current experimental data, and then we study collider signatures in each Higgs sector. In Part I, we focus on the phenomenology of…
If the Universe underwent a cosmic phase transition, it may have left behind a network of cosmic strings. When these strings arise from the breaking of a gauge symmetry, their decay produces a significant stochastic background of…
An interaction between dark matter and dark energy is usually introduced by a phenomenological modification of the matter conservation equations, while the Einstein equations are left unchanged. Starting from some general and fundamental…
The precision era of multi-messenger astronomy, together with modern astrophysical, cosmological, and gravitational wave observations, increasingly points toward the existence of a ``dark" sector that cannot be explained within the…
Despite the great success of the Standard Model of particle physics the nature of Dark Matter still remains unclear. Recently, the idea of the existence of a hidden sector coupling only weakly with the ordinary matter was revitalized and…
(Abridged) Present cosmological constraints and the absence of a direct detection and identification of any dark matter particle candidate leave room to the possibility that the dark sector of the Universe be actually more complex than it…
I present some new perspectives on Dark Matter, Dark Energy and the origin of structure in the Universe. First, I argue that in order to understand the two latter issues, one needs to go beyond a standard point particle effective field…
We present a scenario in which a scalar field dark energy is coupled to the trace of the energy momentum tensor of the baryonic matter fields. In the slow-roll regime, this interaction could give rise to the cosmological features of dark…
Colored dark sectors where the dark matter particle is accompanied by colored partners have recently attracted theoretical and phenomenological interest. We explore the possibility that the dark sector consists of the dark matter particle…
Coupled dark matter-dark energy scenarios are modeled via a dimensionless parameter $\xi$, which controls the strength of their interaction. While this coupling is commonly assumed to be constant, there is no underlying physical law or…
Astrophysical observations provide compelling evidence for gravitationally interacting dark matter in the universe that cannot be explained by the standard model of particle physics. The extraordinary amount of data from the CERN LHC…
Quantum scale invariance in the UV has been recently advocated as an attractive way of solving the gauge hierarchy problem arising in the Standard Model. We explore the cosmological signatures at the electroweak scale when the breaking of…
Flat directions are a generic feature of the scalar potential in supersymmetric gauge field theories. They can arise, for example, from D-terms associated with an extra abelian gauge symmetry. Even when supersymmetry is broken softly, there…
A cosmological model is proposed for the current Universe consisted of non-interacting baryonic matter and interacting dark components. The dark energy and dark matter are coupled through their effective barotropic indexes, which are…
We consider the possible existence of a SM-neutral and light dark sector coupled to the visible sector through irrelevant portal interactions. Scenarios of this kind are motivated by dark matter and arise in various extensions of the…
Superstring theories are very promising theoretically, but the enormous landscape of string vacua and the (likely) very large underlying string scale imply that they may never be tested directly. Nevertheless, concrete constructions…