You can see a clock running backwards in time

TL;DR

This paper discusses how observing a clock running backwards in time is possible without violating causality, emphasizing the distinction between observation and reality in cosmological contexts.

Contribution

It introduces the idea that apparent backwards time flow can occur without causality violations, highlighting observational illusions in cosmology.

Findings

Observers can see clocks run backwards without causality breach

Observation may not reflect actual events at large distances

Implications for cosmological observations and interpretations

Abstract

The epitome of acausal or anti-chronological behaviour would be to see a clock running backwards in time. In this essay we point out that this is indeed possible, but there is no problem with causality. What you see isn't what is really happening. Locally, causality is always respected. However our observation should be cause for pause to astronomers and cosmologists, who strictly observe events occurring at very large distances or very long ago and certainly not locally. It can be that what you see isn't what you necessarily get.