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Discussion: Some Recent Controversy Over the Possibility of Experimentally Determining Isotropy in the Speed of Light

Published online by Cambridge University Press:  01 April 2022

Robert K. Clifton
Robert K. Clifton*
Affiliation:
Department of the History and Philosophy of Science, Cambridge University
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Abstract

The most recent attempt at factually establishing a “true” value for the oneway velocity of light is shown to be faulty. The proposal consists of two round-trip photons travelling first in vacuo and then through a medium of refractive index n before returning to their common point of origin. It is shown that this proposal, as well as a similar one considered by Salmon (1977), presupposes that the one-way velocities of light are equal to the round-trip value. Furthermore, experiments of this type, involving regions of space with varying refractive indices, cannot “single out” any factual value for the Reichenbach-Grünbaum ∊ factor thus posing no threat to the conventionalist thesis.

Type
Discussion
Information
Philosophy of Science , Volume 56 , Issue 4 , December 1989 , pp. 688 - 696
Copyright
Copyright © 1989 by the Philosophy of Science Association

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Footnotes

†

I wish to thank Prof. Kathleen Okruhlik, Philip Catton (both of the University of Western Ontario), Dale Tweed (University of Waterloo) and Prof. Michael Redhead (Cambridge University) for inspiration and criticism. Acknowledgment is also due to the Natural Science and Engineering Research Council of Canada from whom I have received financial support.

References

Brown, H. (forthcoming), “Discussion: Does the Principle of Relativity Imply Winnie's (1970) Equal Passage Times Principle?” forthcoming in Philosophy of Science 57 (June 1990).Google Scholar
Giannoni, C. (1978), “Relativistic Mechanics and Electrodynamics Without One-Way Velocity Assumptions”, Philosophy of Science 45: 17–46.CrossRefGoogle Scholar
Kolen, P., and Torr, D. G. (1982), “An Experiment to Measure the One-Way Velocity of Propogation of Electromagnetic Radiation”, Foundations of Physics 12: 401–411.CrossRefGoogle Scholar
Nissim-Sabat, C. (1984), “A Gedankenexperiment to Measure the One-Way Velocity of Light”, British Journal for the Philosophy of Science 35: 62–64.CrossRefGoogle Scholar
Reichenbach, H. (1958), The Philosophy of Space and Time. New York: Dover.Google Scholar
Salmon, W. (1977), “The Philosophical Significance of the One-Way Speed of Light”, Noûs 11:253–292.CrossRefGoogle Scholar
Stolakis, G. (1986), “Against Conventionalism in Physics”, British Journal for the Philosophy of Science 37: 229–232.CrossRefGoogle Scholar