Related papers: Dark Sectors and New, Light, Weakly-Coupled Partic…
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…
A broad program of searches at high intensity experiments during the coming decade and beyond will sensitively probe new light mediator particles interacting through the minimal renormalizable vector, Higgs, and neutrino portals as well as…
Dark matter can be part of a dark sector with non-minimal couplings to the Standard Model. Compared to many (minimal) benchmark models, such scenarios can result in significant modifications in experimental signatures and strongly impact…
The axion is a light pseudoscalar particle postulated to solve issues with the Standard Model, including the strong CP problem and the origin of dark matter. In recent years, there has been remarkable progress in the physics of axions in…
We examine the ability of future facilities to discover and interpret non-supersymmetric new phenomena. We first explore explicit manifestations of new physics, including extended gauge sectors, leptoquarks, exotic fermions, and technicolor…
Dark matter constitutes $26\%$ of the total energy in our universe, but its nature remains elusive. Among the assortment of viable dark matter candidates, particles and fields with masses lighter than $40 \mathrm{eV}$, called ultralight…
We present some bottom-up motivations of axions and other weakly interacting sub-eV particles (WISPs) coupling to photons. Typically, these light particles are strongly constrained by their production or interaction in astrophysical and…
The Standard Model (SM) of particle physics provides a successful description of fundamental particles and their interactions but fails to explain phenomena such as neutrino oscillations, dark matter (DM), and the baryon asymmetry of the…
This theoretical particle physics thesis is an investigation into old and new symmetries of Nature. Known symmetries and conservation laws serve as a guide for dark and visible sector model building. New symmetries of Nature are proposed,…
Tensions in the measurements of neutron and kaon weak decays, such as of the neutron lifetime, may speak to the existence of new particles and dynamics not present in the Standard Model (SM). In scenarios with dark sectors, particles that…
Cosmology and particle physics are closer today than ever before, with several searches underway at the interface between cosmology, particle physics, and field theory. The mystery of dark matter (DM) is one of the greatest common unsolved…
A simple way to accommodate dark matter is to postulate the existence of a hidden sector. That is, a set of new particles and forces interacting with the known particles predominantly via gravity. In general this leads to a large set of…
The increasing quality of cosmological data has revealed some tensions that could be signalling the necessity of incorporating new physics into our cosmological model. One particularly intriguing possibility is the existence of elastic…
Dark matter (DM) plays a crucial role in explaining the observed astrophysical anomalies, galaxy rotation curves, and other fundamental characteristics of the Universe. Many extensions of the Standard Model (SM), such as the dark…
A new strong interaction sector is proposed as a possible origin for the Dark Energy and Dark matter. It is described by an unbroken gauge group $SU(2)_Z$ which grows strong at a scale $\Lambda_Z \sim 10^{-3} eV$ provided its coupling is of…
We study the possibility that dark matter is a baryon of a new strongly interacting gauge theory, which was introduced in the low energy theory of Cosmological SUSY Breaking (CSB). This particle can fit the observed dark matter density if…
A hidden sector that kinetically mixes with the Minimal Supersymmetric Standard Model provides simple and well-motivated dark matter candidates that possess many of the properties of a traditional weakly interacting massive particle (WIMP).…
We construct a theory in which the solution to the strong CP problem is an emergent property of the background of the dark matter in the Universe. The role of the axion degree of freedom is played by multi-body collective excitations…
Several models of dark matter suggest the existence of dark sectors consisting of SU(3)_C x SU(2)_L x U(1)_Y singlet fields. These sectors of particles do not interact with the ordinary matter directly but could couple to it via gravity. In…
The identity of dark matter is a question of central importance in both astrophysics and particle physics. In the past, the leading particle candidates were cold and collisionless, and typically predicted missing energy signals at particle…