Fermi co-ordinates and relativistic effects in non-inertial frames

H. Nikolic

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arXiv · gr-qc/0009068

Fermi co-ordinates and relativistic effects in non-inertial frames

H. Nikolic

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Abstract

Fermi co-ordinates are proper co-ordinates of a local observer determined by his trajectory in space-time. Two observers at different positions belong to different Fermi frames even if there is no relative motion between them. Use of Fermi co-ordinates leads to several physical conclusions related to relativistic effects seen by observers in arbitrary motion. In flat space-time, the relativistic length seen by an observer depends only on his instantaneous velocity, not on his acceleration or rotation. In arbitrary space-time, for any observer the velocity of light is isotropic and equal to $c$, provided that it is measured by propagating a light beam in a small neighbourhood of the observer. The value of a covariant field measured at the position of the observer depends only on his instantaneous position and velocity, not on his acceleration. The notion of radiation is observer independent. A "freely" falling charge in curved space-time does not move along a geodesic and therefore radiates.

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H. Nikolic. 2000-09-19. Fermi co-ordinates and relativistic effects in non-inertial frames. https://arxiv.org/abs/gr-qc/0009068

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