BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Eric Ling (Rutgers University) DTSTART:20220203T143000Z DTEND:20220203T153000Z DTSTAMP:20260423T023045Z UID:jomarec/14 DESCRIPTION:Title: On the discrete Dirac spectrum of a point electron in the zero-gravity Ke rr-Newman spacetime\nby Eric Ling (Rutgers University) as part of JoMa ReC - Joint Online Mathematical Relativity Colloquium\n\n\nAbstract\nIn re lativistic quantum mechanics\, the point spectrum of the Dirac hamiltonian with a Coulomb potential famously agrees with Sommerfeld’s fine structu re formula for the hydrogen atom. In the Coulomb approximation\, the proto n is assumed to only have a positive electric charge. However\, the physic al proton also appears to have a magnetic moment which yields a hyperfine structure of the hydrogen atom that’s normally computed perturbatively. Aiming towards a non-perturbative approach\, Pekeris in 1987 proposed taki ng the Kerr-Newman spacetime with its ring singularity as a source for the proton’s electric charge and magnetic moment. Given the proton’s mass and electric charge\, the resulting Kerr-Newman spacetime lies well withi n the naked singularity sector which possess closed timelike loops. In 201 4 Tahvildar-Zadeh showed that the zero-gravity limit of the Kerr-Newman sp acetime (zGKN) produces a flat but topologically nontrivial spacetime that ’s no longer plagued by closed timelike loops. In 2015 Tahvildar-Zadeh a nd Kiessling studied the hydrogen problem with Dirac’s equation on the z GKN spacetime and found that the hamiltonian is essentially self-adjoint a nd contains a nonempty discrete spectrum. In this talk\, we show how their ideas can be extended to classify the discrete spectrum completely and re late it back to the known hydrogenic Dirac spectrum but yielding hyperfine -like and Lamb shift-like effects.\n LOCATION:https://researchseminars.org/talk/jomarec/14/ END:VEVENT END:VCALENDAR