Traveler-point dynamics

Phil Fraundorf (1)

1 University of Missouri [St. Louis]

Locally-defined parameters chosen to be minimally frame-variant can be useful for describing motion in accelerated frames and in curved spacetimes. In particular the metric-equation's synchrony-free ``traveler-point parameters'', namely proper-time, plus 3-vectors proper-velocity and proper-force, are useful in curved spacetime because extended arrays of synchronized clocks (e.g. for local measurement of the denominator in $\Delta x / \Delta t$) may be hard to find. Combined with a recognition of improper (geometric) forces, these same parameters can better prepare intro-physics students for their everyday world, as well as for the technological world e.g. of GPS systems where differential aging must be considered explicitly. The approach also suggests a traveler-perspective path to 3-vector simulations that are exact at any speed in flat spacetime, and will soon help frame on-line simulations of interstellar navigation including effects of gravitational fields.

Mots clés: proper time; proper velocity; proper acceleration; proper force

Domaines: Enseignement de la physique [physics.ed-ph]

Phil Fraundorf. Traveler-point dynamics. 2017. ⟨hal-01503971v2⟩