Search results for "Fermi coordinates"
showing 2 items of 2 documents
Motion of an electric charge in a terrestrial laboratory.
1995
The equation of motion for a charge in an electromagnetic field is written in the Fermi coordinates of an observer moving with a constant acceleration g=9.8 m/${\mathrm{s}}^{2}$ (${10}^{\mathrm{\ensuremath{-}}18}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ in units such that c=1). This is involved in the equation of motion not only as a Newtonian term g\ensuremath{\rightarrow}, but also as a relativistic correction of the form ``-2(g\ensuremath{\rightarrow}\ensuremath{\cdot}v\ensuremath{\rightarrow})v\ensuremath{\rightarrow}.'' We have studied the effect of this term under the conditions of an accelerator of particles. To this end, we have considered a constant and uniform magnetic field, a…
Relative velocities for radial motion in expanding Robertson-Walker spacetimes
2011
The expansion of space, and other geometric properties of cosmological models, can be studied using geometrically defined notions of relative velocity. In this paper, we consider test particles undergoing radial motion relative to comoving (geodesic) observers in Robertson-Walker cosmologies, whose scale factors are increasing functions of cosmological time. Analytical and numerical comparisons of the Fermi, kinematic, astrometric, and the spectroscopic relative velocities of test particles are given under general circumstances. Examples include recessional comoving test particles in the de Sitter universe, the radiation-dominated universe, and the matter-dominated universe. Three distinct …