This series consists of talks in the areas of Particle Physics, High Energy Physics & Quantum Field Theory.
The cosmological model based on cold dark matter (CDM) and dark energy has been hugely successful in describing the observed evolution and large scale structure of our Universe. However, at small scales (in the smallest galaxies and at the centers of larger galaxies), a number of observations seem to conflict with the predictions CDM cosmology, leading to recent interest in Warm Dark Matter (WDM) and Self-Interacting Dark Matter (SIDM) models. These small scales, though, are also regions dominated by the influence of baryons.
In the search for dark matter, neutrino experiments can play a key role by doubling as dark matter production and detection experiments. I will describe how the proposed DAEdALUS decay-at-rest neutrino experiment can be used to search for MeV-scale dark matter, with particular emphasis on dark matter produced through a dark photon in rare neutral pion decays. The fact that the dark photon need not be on-shell opens up a wide range of new possibilities for the experimental program of searching for dark matter at neutrino experiments.
Recent comparison between observation and expectation could point to problems with the standard cold, non-interacting dark matter picture, one of which being how small the smallest gravitationally bound dark matter halos are. I will review the cold dark matter picture and the experimental tests. One solution to the problems comes from coupling the dark matter to neutrinos. I will describe the model building requirements of such a coupling and determine how to test this scenario.
Moduli fields with Planck suppressed couplings to light species are ubiquitous in string theory and supersymmetry. These scalar fields are expected to dominate the energy budget in the early universe. Their out-of-equilibrium decays can produce dark matter and baryons. Dark matter generated in this non-thermal manner typically has large annihilation rates that are strongly constrained by indirect detection. The resulting bounds on superpartner masses offer dim prospects for collider discovery of supersymmetry.
A new experiment called PTOLEMY (Princeton Tritium Observatory for Light, Early-Universe, Massive-Neutrino Yield) is under development at the Princeton Plasma Physics Laboratory with the goal of challenging one of the most fundamental predictions of the Big Bang – the present-day existence of relic neutrinos produced less than one second after the Big Bang.
An overview of the latest Higgs physics results from the ATLAS collaboration will be presented. Next year, the Large Hadron collider will restart at a higher collision energy after a 2-year shutdown. The Higgs physics programme for this next data taking period will be discussed.
In the next few years, Advanced LIGO will be the first experiment to detect gravitational waves. Through superradiance of stellar black holes, it may also be the first experiment to discover the QCD axion with decay constant around or above the GUT scale. When an axion's Compton wavelength is comparable to the size of a black hole, the axion binds to the black hole, forming a "gravitational atom". Due to superradiance, the number of axions occupying the bound levels grows exponentially, extracting energy and angular momentum from the black hole.