Grant: Subatomic Physics Envelope - Project

Antihydrogen physics has entered the precision measurement era. Over the past few years, ALPHA demonstrated a long list of experimental firsts. We have developed methods that enable us to accumulate thousands of antihydrogen atoms [Nature Comm. 2017]; We observed the hyperfine spectrum of antihydrogen [Nature 2018]; We demonstrated laser spectroscopy of antihydrogen [Nature 2017] and measured the 1s-2s interval with 10-12 level precision [Nature 2018]; we observed 1s-2p Lyman-alpha transitions in antihydrogen [Nature 2018], probed the fine structure splitting and Lamb shift [Nature 2020]. Importantly, during the current funding cycle, we have achieved two milestones once deemed a 'dream' in the field: laser cooling of antihydrogen [Nature 2021], and the direct observation of the gravitational force on antihydrogen [Nature 2023]. The award-winning Canadian contingent - ALPHA-Canada - constitutes more than one-third of the full ALPHA collaboration, and has played a leading role in subatomic, microwave physics, laser cooling, and gravity efforts from the outset. Our Highly Qualified Personnel (HQP) trainees are winning many awards and fellowships, and finding highly impactful positions, both in academia and industry. Building on a long track record of success, we propose an ambitious program of fundamental physics with trapped antihydrogen: Our primary goals are to realize, within the next 3 years, 5-to-10-fold improvements in the precision of spectroscopic and gravitational tests of matter-antimatter symmetries, and to continue driving innovative technological developments to further push the frontiers of antihydrogen physics. Through these pursuits, we provide exceptional and inclusive training for our HQP.