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. 2022 Jul 24;24(8):1022.
doi: 10.3390/e24081022.

Memory and Entropy

Carlo Rovelli  1   2   3
Affiliations

Memory and Entropy

Carlo Rovelli. Entropy (Basel). .

Abstract

I study the physical nature of traces. Surprisingly, (i) systems separation with (ii) temperature differences and (iii) long thermalization times are sufficient conditions to produce macroscopic traces. Traces of the past are ubiquitous because these conditions are largely satisfied in our universe. I quantify these thermodynamical conditions for memory and derive an expression for the maximum amount of information stored in such memories as a function of the relevant thermodynamical parameters. This mechanism transforms low entropy into available information. I suggest that all macroscopic information has this origin in past low entropy.

Keywords: information.; metastable systems; traces.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
The model for memory. The cold damped pendulums and fast hot balls. The wide oscillation of a single oscillating pendulum is a trace of a past interaction between a ball and a pendulum.
See this image and copyright information in PMC

References

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    1. Rovelli C. The Order of Time. Riverhead; New York, NY, USA: 2018.
    1. Einstein A., Tolman R., Podolsky B. Knowledge of past and future in quantum mechanics. Phys. Rev. 1931;37:780. doi: 10.1103/PhysRev.37.780. - DOI
    1. Rovelli C. An argument against the realistic interpretation of the wave function. Found. Phys. 2016;46:1229–1237. doi: 10.1007/s10701-016-0032-9. - DOI
    1. Albert D.Z. After Physics. Harvard University Press; Cambridge, MA, USA: 2015. The Difference between the Past and the Future. Chapter 5.

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