Graduate Einstein's Elevator Trajectories: Desloge & Philpott 1987, Hamilton 1978

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The discussion focuses on the trajectories of light and particles in a uniformly accelerated reference frame, referencing key papers by Desloge & Philpott (1987) and Hamilton (1978). It raises questions about the nature of trajectories when initial velocities are non-vertical, specifically how they appear on a vertical wall of an elevator. The conversation highlights that particles in a homogeneous electric field exhibit hyperbolic trajectories, while photons appear to follow circular paths in an accelerated elevator. The relationship between these trajectories and Rindler coordinates is also noted, emphasizing the geometric nature of the paths in a Lorentzian framework. Understanding these dynamics is crucial for further exploration of relativistic motion in accelerated frames.
Mathieu Rouaud
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Newton's theory predicts parabolic trajectories. But what kind of trajectories within the framework of Special Relativity?
Hello,
Some papers describe the vertical motion of a ray of light or a non-zero mass particle in a uniformly accelerated reference frame in special relativity:
  • Desloge, E. A., & Philpott, R. J. (1987). Uniformly accelerated reference frames in special relativity. American Journal of Physics, 55(3), 252–261. https://doi.org/10.1119/1.15197 (world lines on page 258)
  • Hamilton, J. D. (1978). The uniformly accelerated reference frame. American Journal of Physics, 46(1), 83–89. https://doi.org/10.1119/1.11169 (world lines for a ray of light on page 85, for a massive particle on page 86)
But in the case of a non-vertical initial velocity what is the trajectory? What kind of curve does a particle draw on a vertical wall of the elevator? Do you know reference papers or books on this subject?
Thank you for your answers.
 
Physics news on Phys.org
A point particle in a homogeneous electric field, neglecting radiation reaction, realizes a particle with constant proper acceleration. The trajectories are hyperbolae.
 
Wikipedia (Rindler coordinates): "we obtain a picture which looks suspiciously like the family of all semicircles through a point and orthogonal to the Rindler horizon"
Thus, the trajectories of photons in the accelerated elevator seem to be circular!
 
Mathieu Rouaud said:
Wikipedia (Rindler coordinates): "we obtain a picture which looks suspiciously like the family of all semicircles through a point and orthogonal to the Rindler horizon"
Thus, the trajectories of photons in the accelerated elevator seem to be circular!
Semi-circular, yes. Given of course a very large elevator where spacetime is still flat.
 
Well, but circles in a Lorentzian plane are in fact hyperbolae (or light cones), namely (in "Minkoski-Cartesian coordinates")
$$\eta_{\mu \nu} x^{\mu} x^{\nu}=\text{const}.$$
See the picture in Wikipedia just close the quoted passage.
 
In an inertial frame of reference (IFR), there are two fixed points, A and B, which share an entangled state $$ \frac{1}{\sqrt{2}}(|0>_A|1>_B+|1>_A|0>_B) $$ At point A, a measurement is made. The state then collapses to $$ |a>_A|b>_B, \{a,b\}=\{0,1\} $$ We assume that A has the state ##|a>_A## and B has ##|b>_B## simultaneously, i.e., when their synchronized clocks both read time T However, in other inertial frames, due to the relativity of simultaneity, the moment when B has ##|b>_B##...

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