10.57647/jtap.2026.8609.0307

The One-Way Light Speed May be Measurable: Non-Equivalence of the Lorentz Transformations and Transformations that Preserve Simultaneity and Spacetime Continuity

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  • Stephan Gift1,
  • Gianfranco Spavieri*2,
  1. Department of Electrical and Computer Engineering, University of the West Indies, St. Augustine, Trinidad and Tobago
  2. Centro de Física Fundamental, Universidad de Los Andes, Mérida, 5101 Venezuela

Received: 2025-11-02

Revised: 2025-11-21

Accepted: 2025-12-17

Published in Issue 2026-06-30

Published Online: 2026-01-20

Copyright (c) 2026 Stephan Gift, Gianfranco Spavieri (Author)

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This work is licensed under a Creative Commons Attribution 4.0 International License.

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1.
Gift S, Spavieri G. The One-Way Light Speed May be Measurable: Non-Equivalence of the Lorentz Transformations and Transformations that Preserve Simultaneity and Spacetime Continuity. J Theor Appl phys. 2026 Jun. 30;20(3). Available from: https://oiccpress.com/jtap/article/view/8609
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Abstract

Based on our analysis of the GPS and other physical effects, we confirm the well-known view that the Lorentz transformations (LT) fail to interpret light propagation along a closed moving contour. We show in detail that, with the LT based on light speed invariance, in the standard linear Sagnac effect a photon traveling at the local speed c cannot cover the whole closed contour in the measured interval T. Thus, the LTs imply a breach in spacetime continuity related to the adoption of relative simultaneity. Making use of internal synchronization procedures a priori not equivalent to Einstein synchronization, in principle it is possible to test Lorentz and light speed invariance and confirm, or not, the contended equivalence between relative and absolute simultaneity.

Keywords

  • One-way speed of light,
  • Sagnac effect,
  • Relative simultaneity,
  • Lorentz invariance,
  • Foundations of relativity theory
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