International Journal of Physics
ISSN (Print): 2333-4568 ISSN (Online): 2333-4576 Website: Editor-in-chief: B.D. Indu
Open Access
Journal Browser
International Journal of Physics. 2013, 1(5), 106-109
DOI: 10.12691/ijp-1-5-2
Open AccessArticle

SR Equations without Constant One-Way Speed of Light

Zhiliang Cao1, and Henry Gu Cao2

1J.P.Morgan Chase

2Deerfield High School, Deerfield

Pub. Date: September 16, 2013

Cite this paper:
Zhiliang Cao and Henry Gu Cao. SR Equations without Constant One-Way Speed of Light. International Journal of Physics. 2013; 1(5):106-109. doi: 10.12691/ijp-1-5-2


A constant one-way light speed is essential for the Theory of Relativity. This detailed study examines two postulates of Special Relativity and concludes that the claim of “constant one-way speed of light” contradicts itself. The equations of Special Relativity are foundations of many physics theories. The findings on controversial Relativity postulates shake the foundation of these theories. Fortunately, equations similar to Special Relativity equations can be derived, assuming that two-way light speed is constant, without the use of Special Relativity Postulates. These new equations provide a better foundation that is compatible with the correct existing physics theories. There is no threat of invalidating all existing physics theories, only incorrect ones. Instead, we can take a new look at some fundamental questions shared among physicists.

relativity physics unified theory one-way speed of light

Creative CommonsThis work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit


Figure of 4


[1]  Einstein A. (1916 (translation 1920)), Relativity: The Special and General Theory, : H. Holt and Company.
[2]  Planck, Max (1906), "The Measurements of Kaufmann on the Deflectability of ß-Rays in their Importance for the Dynamics of the Electrons", Physikalische Zeitschrift 7: 753-761
[3]  Miller, Arthur I. (1981), Albert Einstein's special theory of relativity. Emergence (1905) and early interpretation (1905-1911).
[4]  Will, Clifford M (August 1, 2010). "Relativity". Grolier Multimedia Encyclopedia. Retrieved 2010-08-01.
[5]  Will, Clifford M (August 1, 2010). "Space-Time Continuum". Grolier Multimedia Encyclopedia. Retrieved 2010-08-01.
[6]  Will, Clifford M (August 1, 2010). "Fitzgerald–Lorentz contraction". Grolier Multimedia Encyclopedia. Retrieved 2010-08-01.
[7]  Einstein, Albert (November 28, 1919). "Time, Space, and Gravitation". The Times.
[8]  Feynman, Richard Phillips; Morínigo, Fernando B.; Wagner, William; Pines, David; Hatfield, Brian (2002). Feynman Lectures on Gravitation. West view Press. p. 68.
[9]  Roberts, T; Schleif, S; Dlugosz, JM (ed.) (20 07). "What is the experimental basis of Special Relativity?". Usenet Physics FAQ. University of California, Riverside. Retrieved 2010-10-31.
[10]  Michael Tooley (2000). Time, tense, and causation. Oxford University Press. p. 350.
[11]  Conventionality of Simultaneity entry by Allen Janis in the Stanford Encyclopedia of Philosophy, 2010.
[12]  Jong-Ping Hsu, Yuan-Zhong Zhang (2001). Lorentz and Poincaré Invariance: 100 Years of Relativity. World Scientific.
[13]  Will, C.M (2006). "Special Relativity: A Centenary Perspective". In T. Damour, O. Darrigol, B. Duplantier und V. Rivasseau. Poincare Seminar 2005. Basel: Birkhauser. pp. 33–58. arXiv:gr-qc/0504085.17th General Conference on Weights and Measures (1983), Resolution 1,Zhang (1997), p 24.
[14]  Will, Clifford M. (1992). "Clock synchronization and isotropy of the one-way speed of light". Physical Review D 45 (2): 403-411.
[15]  Hafele, J. C.; Keating, R. E. (July 14, 1972). "Around-the-World Atomic Clocks: Predicted Relativistic Time Gains". Science 177 (4044): 166-168.
[16]  C.O. Alley, in NASA Goddard Space Flight Center, Proc. of the 13th Ann. Precise Time and Time Interval (PTTI) Appl. and Planning Meeting, p. 687-724, 1981, available online.
[17]  Giulini, Domenico (2005). "Synchronization by slow clock-transport". Special Relativity: A First Encounter. 100 years since Einstein. Oxford University Press. ISBN 0191620866. Special Relativity: A First Encounter at Google Books.
[18]  Winnie, J. A. A. (1970). "Special Relativity without One Way Velocity Assumptions". Philosophy of Science 37: 81-99, 223-38.
[19]  Debs, Talal A.; Redhead, Michael L. G. (1996). "The twin "paradox" and the conventionality of simultaneity". American Journal of Physics 64 (4): 384-392.
[20]  Bailey et al (1977). "Measurements of relativistic time dilatation for positive and negative muons in a circular orbit". Nature 268 (5618): 301-305.
[21]  Wesley C. Salmon (1977). "The Philosophical Significance of the One-Way Speed of Light". Noûs 11 (3): 253-292.
[22]  Ohanian, Hans C. (2004). "The role of dynamics in the synchronization problem". American Journal of Physics 72 (2): 141-148.
[23]  Ohanian, Hans C. (2005). "Reply to "Comment(s) on 'The role of dynamics in the synchronization problem'," by A. Macdonald and A. A. Martínez". American Journal of Physics 73 (5): 456-457.
[24]  Martínez, Alberto A. (2005). "Conventions and inertial reference frames". American Journal of Physics 73 (5): 452-454.
[25]  MacDonald, Alan (2004). "Comment on "The role of dynamics in the synchronization problem," by Hans C. Ohanian". American Journal of Physics 73 (5): 454-455.
[26]  Iyer, Chandru; Prabhu, G. M. (2010). "A constructive formulation of the one-way speed of light". American Journal of Physics 78 (2): 195-203.
[27]  Greaves, E. D.; Rodríguez, An Michel; Ruiz-Camacho, J. (2009), "A one-way speed of light experiment", American Journal of Physics 77 (10): 894-896.
[28]  Finkelstein, J. (2009), "One-way speed of light?", American Journal of Physics 78 (8): 877.
[29]  Roberts, Schleif (2006): Relativity FAQ, One-Way Tests of Light-Speed Isotropy.
[30]  Mansouri R., Sexl R.U. (1977). "A test theory of special relativity: II. First order tests". General. Relat. Gravit. 8 (7): 515-524.
[31]  Krisher et al. (1990). "Test of the isotropy of the one-way speed of light using hydrogen-maser frequency standards". Physical Review D 42 (2): 731-734.
[32]  Vessot et al (1980). "Test of relativistic gravitation with a space-borne hydrogen maser". Physical Review Letters 45 (29): 2081-2084.
[33]  Riis et al (1988). "Test of the Isotropy of the speed of light using fast-beam laser spectroscopy". Physical Review Letters 60 (11): 81-84.
[34]  Nelson et al. (1992). "Experimental comparison of time synchronization techniques by means of light signals and clock transport on the rotating earth". Proceedings of the 24th PTTI meeting 24: 87-104.
[35]  Wolf, Peter; Petit, Gérard (1997). "Satellite test of special relativity using the global positioning system". Physical Review A 56 (6): 4405-4409.
[36]  Brecher, K. (1977), "Is the speed of light independent of the velocity of the source", Physical Review Letters 39: 1051-1054.
[37]  Alväger, T.; Nilsson, A.; Kjellman, J. (1963), "A Direct Terrestrial Test of the Second Postulate of Special Relativity", Nature 197 (4873): 1191.
[38]  Amelino-Camelia, G (2009). "Astrophysics: Burst of support for relativity". Lay summary – Nature (19 November 2009). Nature 462 (7271): 291-292.
[39]  Laurent et al. (2011). "Constraints on Lorentz Invariance Violation using integral/IBIS observations of GRB041219A". Physical Review D 83 (12): 121301.
[40]  Kostelecký, V. Alan; Mewes, Matthew (2002). "Signals for Lorentz violation in electrodynamics". Physical Review D 66 (5): 056005.