Ontological Study on Time in Terms of Contemporary Physics

Abstract

This paper examines the change of the concept of time and its ontological meaning in physics, focusing on modern physics. The concept of absolute time was presented in Newton's classical physics, and since then, the concepts of relativistic time and quantized time have been introduced in Einstein's theory of relativity and quantum gravity theory, respectively. This change raises question about the true concept of time in the universe. In this paper, in order to find an answer to this question, the ontological meaning of the concept of time presented by each theory is compared. First, the concept of absolute time is regarded as a concept of time that we usually accept, and it is revealed that the meanings of uniqueness, independent reality, separability, directionality, continuity, uniformity, transcendence, and objectivity are included in it. And, in the concepts of relativistic time and quantized time, these characteristics are dismantled one by one. Nevertheless, whether the concept of time in the world we experience is compatible with the concept of quantized time is investigated through the thermal time hypothesis. Finally, we examine the implications of time quantization in philosophy of science, even though (loop) quantum gravity theory is a theoretical imagination that has not yet been empirically verified.