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Induced Matter and Particle Motion in Non-Compact Kaluza-Klein Gravity

Andrew P. Billyard·William N. Sajko
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Abstract

We examine generalizations of the five-dimensional canonical metric by including a dependence of the extra coordinate in the four-dimensional metric. We discuss a more appropriate way to interpret the four-dimensional energy-momentum tensor induced from the five-dimensional space-time and show it can lead to quite different physical situations depending on the interpretation chosen. Furthermore, we show that the assumption of five-dimensional null trajectories in Kaluza-Klein gravity can correspond to either four-dimensional massive or null trajectories when the path parameterization is chosen properly. Retaining the extra-coordinate dependence in the metric, we show the possibility of a cosmological variation in the rest masses of particles and a consequent departure from four-dimensional geodesic motion by a geometric force. In the examples given, we show that at late times it is possible for particles traveling along 5D null geodesics to be in a frame consistent with the induced matter scenario.

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Andrew P. Billyard, William N. Sajko. 2001-05-20. Induced Matter and Particle Motion in Non-Compact Kaluza-Klein Gravity. https://doi.org/10.1023/a%3A1013046825852

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