Yue Zhang
University of Carleton

Abstract

The recent discoveries of the Higgs boson and gravitational waves marked the triumph of two cornerstones of modern physics, the standard model of elementary particles and Einstein’s theory of gravity. However, overwhelming evidence from cosmology suggests that the standard model is inadequate for understanding our universe. There is stuff gravitating that we cannot see with light. In particular, the identity of dark matter which comprises eighty-percent of the matter in the universe, remains unknown. In this talk, I will discuss potential intimate connections between dark matter and neutrinos from early universe to the present. I will tell a new story of an old dark matter candidate, the sterile neutrino, and highlight how new theories for neutrino self-interaction are driving us to novel frontiers of dark matter searches.

Nobel Laureate and Professor Emeritus Art McDonald
Queen's University

Nobel Research Public Lecture

Katie Mack
NCSU

Abstract:

TBA

Miriam Diamond
University of Toronto

Abstract:

The leading dark matter (DM) paradigm over the past few decades has been that of a Weakly Interacting Massive Particle with a mass of tens of GeV to a few TeV. But in light of recent experimental constraints, attention is increasingly turning to models with lower-mass DM, especially in the context of a “dark sector” featuring multiple DM particle species. Probing such models requires exploiting complementarity between different types of DM searches, where electron-beam fixed-target experiments play an important role in the DM mass range of a few to hundreds of MeV. These experiments seek to generate dark sector particles, such as dark photons, via electron-nucleus scattering and emission processes analogous to standard bremsstrahlung. Identifying the visible decay products of the dark sector particles, such as electron-positron pairs, requires precise reconstruction of narrow mass resonances and/or displaced vertices; accounting for invisible decay products requires precise missing energy and/or momentum measurements. In this talk, I will give an overview of the landscape of current and planned fixed-target DM searches, with the Heavy Photon Search (HPS) and its planned successor LDMX (Light Dark Matter eXperiment) as specific examples.

Ravijet Uppu
University of Iowa

Abstract

Photons are essential for transmitting quantum information given the ease with which we can generate, manipulate, and detect them. While several physical systems such as atoms, ions, and quantum dots were explored as candidate photon sources over the past few decades, none could achieve the steep performance metrics necessary for quantum advantage demonstrations. A simple reason behind the shortcoming is inefficiency, i.e., the ease with which we could lose a photon. I will illustrate how a carefully designed nanophotonic light-matter interface can overcome these shortcomings to realize an efficient and coherent single-photon source that will enable transformative capabilities in photonic quantum technologies. I will conclude with a discussion on the new avenues that wavefront control opens in nanophotonic light-matter interfaces.

Katelin Schutz
University of McGill

Abstract

How different would our Universe look with the addition of extra particles and forces beyond what we know? We already have ample gravitational evidence for at least one invisible component of matter that has properties unlike anything we have previously discovered. This dark matter is often assumed to be made of a single species of relatively inert particles but there is a much richer range of possibilities, including scenarios where dark matter is part of a “dark sector” including other auxiliary particles and forces. If there are dark forces affecting the distribution of dark matter in our Universe, then that distribution will gravitationally affect the visible matter that we can see. In this colloquium I will show how this gravitational footprint can reveal the internal properties of dark sectors where dark matter can dissipate energy, can scatter with itself (elastically or inelastically), can be wavelike on astrophysical scales, or can be born non-thermally in the moments after the Big Bang. In showing how these possibilities can be tested empirically, I will emphasize the constraining power of diverse astrophysical systems including the local Milky Way, nearby dwarf galaxies, distant galaxies and galaxy clusters, large-scale cosmological structure, and the cosmic microwave background.