English

Making the Relativistic Dynamics Equation Covariant: Explicit Solutions for Motion under a Constant Force

General Physics 2015-06-12 v1

Abstract

We derive a 4D covariant Relativistic Dynamics Equation. This equation canonically extends the 3D relativistic dynamics equation F=dpdt\mathbf{F}=\frac{d\mathbf{p}}{dt}, where F\mathbf{F} is the 3D force and p=m0γv\mathbf{p}=m_0\gamma\mathbf{v} is the 3D relativistic momentum. The standard 4D equation F=dpdτF=\frac{dp}{d\tau} is only partially covariant. To achieve full Lorentz covariance, we replace the four-force FF by a rank 2 antisymmetric tensor acting on the four-velocity. By taking this tensor to be constant, we obtain a covariant definition of uniformly accelerated motion. This solves a problem of Einstein and Planck. We compute explicit solutions for uniformly accelerated motion. The solutions are divided into four Lorentz-invariant types: null, linear, rotational, and general. For null acceleration, the worldline is cubic in the time. Linear acceleration covariantly extends 1D hyperbolic motion, while rotational acceleration covariantly extends pure rotational motion.

Keywords

Cite

@article{arxiv.1212.2959,
  title  = {Making the Relativistic Dynamics Equation Covariant: Explicit Solutions for Motion under a Constant Force},
  author = {Yaakov Friedman and Tzvi Scarr},
  journal= {arXiv preprint arXiv:1212.2959},
  year   = {2015}
}

Comments

16 pages. arXiv admin note: substantial text overlap with arXiv:1105.0492

R2 v1 2026-06-21T22:53:32.417Z