Journal of Physics Conference Series

No time for isolated clocks

K. L. H. Bryan, A. J. M. Medved

Published Sep 1, 2019• 0 citations

Abstract

Abstract The Wheeler-DeWitt equation provides a model of the Universe as a timeless, isolated system. Page and Wootters developed the conditional probability interpretation (CPI) to account for the experience of time within this timeless model by identifying part of the Universe as the clock. In resolving criticisms of the CPI, some investigators have since concluded that the clock must be completely isolated from the remainder of the Universe. This isolation has also been used to reinforce the conclusion that time must be an illusion. However, some interactions must exist between all subsystems of the Universe as gravitational effects, however weak, cannot be shielded. Here, we present the results of an investigation which used a toy model to consider the implications of including interactions. Although counter intuitive, their inclusion is seen to directly correlate with the accuracy of measurements of the clock state. The case is then made that, if interactions are indeed a necessary feature of the CPI, the viability of treating time as an illusion needs to be reconsidered. We conclude that the experience of time can be interpreted as a real phenomenon, which naturally incorporates an arrow of time, once interactions are taken seriously in the CPI paradigm.

DOI: 10.1088/1742-6596/1275/1/012037

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