28-30 September 2017
Hotel Posada San Francisco, Tlaxcala
America/Mexico_City timezone
Contribution
Hotel Posada San Francisco, Tlaxcala
Extracting Geometry from Quantum Spacetime: Obstacles down the road.
Speakers
- Prof. Chryssomalis CHRYSSOMALAKOS
Description
Any acceptable version of a quantum theory of gravity must include, in the
appropriate limit, the recovery of the classical spacetime. Moreover, the
spacetime notion itself should be intrinsically tied to the behavior of the matter
that probes it. We consider some of difficulties that would be confronted in
attempting this enterprise. The problems we uncover seem to go beyond the
technical level to the point of questioning the overall feasibility of the project. The
main issue is related to the fact that, in the quantum theory, it is not possible to
assign a trajectory to a physical object, and, on the other hand, according to the
basic tenants of the geometrization of gravity, it is precisely the trajectories of free
localized objects that must somehow define the spacetime geometry. This
indicates the need to revise the standard geometrical concepts, and to explore
the corresponding notions that could have operational meaning. The insights
gained in this analysis should be relevant to those interested in the quest for a
quantum theory of gravity and might help refocus some of its goals.