Space time and the passage of time

TL;DR

This paper defends the view that time exists and flows, proposing an Evolving Block Universe model within General Relativity that accounts for quantum uncertainty and aligns with human perception of time.

Contribution

It introduces an Evolving Block Universe model that captures the flow of time and its physical basis, integrating quantum effects and perceptual evidence.

Findings

Time both exists and flows according to the EBU model.

Surfaces of constant time are uniquely determined in realistic spacetime models.

Quantum uncertainty influences the evolution of spacetime structure.

Abstract

This paper examines the various arguments that have been put forward suggesting either that time does not exist, or that it exists but its flow is not real. I argue that (i) time both exists and flows; (ii) an Evolving Block Universe (`EBU') model of spacetime adequately captures this feature, emphasizing the key differences between the past, present, and future; (iii) the associated surfaces of constant time are uniquely geometrically and physically determined in any realistic spacetime model based in General Relativity Theory; (iv) such a model is needed in order to capture the essential aspects of what is happening in circumstances where initial data does not uniquely determine the evolution of spacetime structure because quantum uncertainty plays a key role in that development. Assuming that the functioning of the mind is based in the physical brain, evidence from the way that the mind apprehends the flow of time prefers this evolving time model over those where there is no flow of time.