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Previous Michelson Postdoctoral Prize Lectureships

Oct 13, 2014 , 12:30 PM in Miller Room, Rock 221

Amar Vutha, York University

How big is the proton anyway?

The proton is a bound state of quarks and gluons, described by the low-energy limit of quantum chromodynamics. Recent measurements using muonic hydrogen have, however, called our understanding of proton physics into question. In this first lecture, I will describe the significant discrepancy that exists between the recent muonic hydrogen measurements and previous measurements on protons -- this is the // proton radius puzzle //. In the absence of any feasible theoretical solutions, new experiments might provide the best clues. I shall describe some of the experiments that are attempting to shed light on this puzzle, including our ongoing efforts to measure the proton radius via the Lamb shift in hydrogen atoms.
Host: Harsh Mathur