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The cosmological origin of time-asymmetry

Mario Castagnino·Luis Lara·Olimpia Lombardi
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Abstract

In this paper we address the problem of the arrow of time from a cosmological point of view, rejecting the traditional entropic approach that defines the future direction of time as the direction of the entropy increase: from our perspective, the arrow of time has a global origin and it is an intrinsic, geometrical feature of space-time. Time orientability and existence of a cosmic time are necessary conditions for defining an arrow of time, which is manifested globally as the time-asymmetry of the universe as a whole, and locally as a time-asymmetric energy flux. We also consider arrows of time of different origins (quantum, electromagnetic, thermodynamic, etc.) showing that they can be non-conventionally defined only if the geometrical arrow is previously defined.

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Mario Castagnino, Luis Lara, Olimpia Lombardi. 2002-11-25. The cosmological origin of time-asymmetry. https://doi.org/10.1088/0264-9381%2F20%2F2%2F310

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