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arXiv · 2609.00229

Dimensional reduction associated with unchanged direction trajectories in flat fiber Robertson Walker spacetimes

D. de la Fuente·R. M. Rubio·J. Torrente-Teruel
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Abstract

In this article, we establish a new dimensional reduction result in (Galilean or Lorentzian) Robertson Walker spacetimes with Euclidean fiber. In this context, we prove that every unchanged direction observer can be embedded into a three dimensional totally geodesic timelike submanifold.

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D. de la Fuente, R. M. Rubio, J. Torrente-Teruel. 2026-08-31. Dimensional reduction associated with unchanged direction trajectories in flat fiber Robertson Walker spacetimes. https://arxiv.org/abs/2609.00229

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