Research

I investigate aspects of particle physics, astrophysics, quantum field theory, and cosmology. Below I have categorized my research with links to selected papers.

1. Searching for Dark Matter Using Neutron Stars 

Old neutron stars by Earth could serve as excellent dark matter detectors. Neutron stars are the densest known objects that aren’t black holes, and as a consequence can accelerate dark matter to nearly the speed of light. This neutron star gravitational  acceleration gives dark matter lots of kinetic energy which can be converted to heat energy detectable with infrared telescopes. A dark matter heated neutron star near Earth could provide the first discovery of dark matter’s interactions.

2. Particle Theory at Very Sensitive Detectors and Colliders

While there are many excellent searches for dark matter and new physics underway, I have helped develop a number of new methods to seek out new physics in both very sensitive and very high energy experiments.

 (with Queen’s Postdoc Ningqiang Song)

 (with Queen’s Postdoc Ningqiang Song and PhD Amit Bhoonah)

 (with Queen’s PhD Ben Broerman)

 (with Queen’s PhD Ben Broerman)

3. Cosmological Connections to Particle Physics

There are connections between laboratory tests of particle physics here on Earth and the earliest moments of our universe. To advance our understanding of both, we have to increase our sensitivity to the behavior of physics at extremes: the highest energies, the rarest fluxes of particles, and the most improbable quantum processes.

(with Queen’s Postdoc Ningqiang Song, PhD Amit Bhoonah, and MSc Simran Nerval)

 (with Queen’s Postdoc Beth Gould)

(with Queen’s Postdoc Beth Gould)

4. Gas Clouds, Planets, Space Stations, and Dark Matter

Dark matter’s interactions could heat up interstellar gas clouds or the deep interior of planets like Earth and Mars. Gas clouds in particular, have provided a compelling new method to search for super-large and super-light dark matter, including ethereally elusive dark photon dark matter and ultra-massive composite dark matter.

 (with Queen’s Postdoc Sarah Schon and PhD Amit Bhoonah)

 (with Queen’s MSc Alan Goodman, Undergrads Andrew Buchanan and Eesha Lodhi)

 (with Queen’s Postdoc Sarah Schon and PhD Amit Bhoonah)

5. Dark Matter and Type Ia Supernovae

Asymmetric dark matter, or dark matter that has an antimatter partner (just like electrons and protons have), may be the ignition source for Type Ia Supernovae. Using the Type Ia explosions of old white dwarf stars, we can test certain dark matter properties.

(with Queen’s PhD Javier Acevedo)

6. Dark Matter and Disappearing Pulsars

Dark matter may be converting pulsars (a kind of neutron star) near the center of the Milky Way into black holes. There are ways to test this hypothesis using gravitational wave observatories,  neutron star age estimates, neutron star mergers in distant galaxies, and even the production of gold and other “r-process” elements in dwarf galaxies. This intriguing dark matter black hole formation process in neutron stars provides a way to test some dark matter models.