Find an alternative spacetime geometry for electromagnetism

Construct or rule out a geometry independent of the charge-to-mass ratio that geometrizes electromagnetic motion while satisfying a universal spacetime criterion for local inertial frames.

Background

The manuscript constructs a charge-dependent kinematic structure and a corresponding nonlinear transport, but finds that particles with different charge-to-mass ratios do not share the same inertial motions. Consequently, the resulting structures fail the universality criterion used to identify spacetime structure.

The authors explicitly leave unresolved whether some alternative construction could geometrize electromagnetism without producing a separate effective inertial structure for each charge-to-mass ratio.