Talk detail

Participant	Singh, Dinesh
Institution	University of Regina - 3737 Wascana Parkway - Regina - Saskatchewan - Canada

Session	PT6	Accepted		Order	Time
Talk	Oral abstract	Title	MPD Particle Motion in Perturbed Space-Time Backgrounds
Coauthors
Abstract	This presentation entails an exploration of Mathisson-Papapetrou-Dixon (MPD) particle motion in perturbed space-time backgrounds within two contexts, based upon an analytic perturbative approach to the MPD equations available in the literature. The first context is to examine how a two-body MPD system in the presence of a strong gravitational background interacts with each other in terms of the Raychaudhuri equation, and then separately via the generalized Jacobi equation for tidal dynamics. This context shows how the presence of a neighbouring MPD particle locally generates an Einstein-Cartan interaction with induced torsion, yielding an instantaneous Riemann-Cartan U4 geometry experienced by the second MPD particle. The second context is to describe the motion of a single MPD particle in a gravitationally perturbed background using the variational principle to extract the gravitational self-force effects due to both particle mass and spin, and also account for radiation reaction to leading-order in the space-time perturbation.
Pdf file

Session	QG2	Accepted		Order	Time
Talk	Oral abstract	Title	Local Space-Time Curvature Effects on Quantum Orbital Angular Momentum
Coauthors
Abstract	This paper claims that local space-time curvature can non-trivially contribute to the properties of orbital angular momentum in quantum mechanics. Of key importance is the demonstration that an extended orbital angular momentum operator due to gravitation can identify the existence of orbital states with half-integer projection quantum numbers "m" along the axis of quantization, while still preserving integer-valued orbital quantum numbers "l" for a simply connected topology. The consequences of this possibility are explored in depth, noting that the half-integer "m" states vanish as required when the locally curved space-time reduces to flat space-time, fully recovering all established properties of orbital angular momentum in this limit. In particular, it is shown that a minimum orbital number of "l = 2" is necessary for the gravitational interaction to appear within this context, in perfect correspondence with the spin-2 nature of linearized general relativity.
Pdf file