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arXiv · 1306.0338

Instants in physics - point mechanics and general relativity

Domenico Giulini
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Abstract

Theories in physics usually do not address ``the present''or ``the now''. However, they usually have a precise notion of an ``instant'' (or state). I review how this notion appears in relational point mechanics and how it suffices to determine durations - a fact that is often ignored in modern presentations of analytical dynamics. An analogous discussion is attempted for General Relativity. Finally I critically remark on the difference between relationalism in point mechanics and field theory and the problematic foundational dependencies between fields and spacetime.

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Domenico Giulini. 2013-06-03. Instants in physics - point mechanics and general relativity. https://arxiv.org/abs/1306.0338

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