# Fundamental Irreversibility: Planckian or Schrödinger–Newton?

## Abstract

**:**

## 1. Introduction

## 2. Irreversibility at Planck Scale

## 3. Irreversibility in the Schrödinger–Newton Context

## 4. Planck Scale or Schrödinger–Newton Context?

## 5. Concluding Remarks

## Funding

## Acknowledgments

## Conflicts of Interest

## Appendix A

11^{10}Aharonov: His office and desk are almost empty, no personal library, no paper piles. He is at most 50 or so. He sits behind the desk, smokes a long fat cigar, makes a phone call, and asks that I take a seat.We await David Bohm, who I will also be introduced to. Until then, I can unfold my quantum-gravity idée fix. David Bohm arrives. He is at least in his 60s, but could be 70. I am listening as Aharonov explains the superstring to Bohm who is repeatedly asking questions. Finally, I also communicate my layman’s views; Bohm’s criticism is also akin. Aharonov allows me to speak, but first tells Bohm with hellish intensively what he could not have heard. Aharonov dislikes gravitational noise; he prefers dynamics. However, at the end, my master equation and the pure state representation may have caught him a bit. He understood everything very well, he spoke steadily, with real firmness and organization.He got two offprints (localization + orthog.)Peres will send money for me.13^{30}We say goodbye.Left margin: Bohm looked at the master equation intently! Immediately, he also knew that decoherence ≠ reduction.

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Diósi, L. Fundamental Irreversibility: Planckian or Schrödinger–Newton? *Entropy* **2018**, *20*, 496.
https://doi.org/10.3390/e20070496

**AMA Style**

Diósi L. Fundamental Irreversibility: Planckian or Schrödinger–Newton? *Entropy*. 2018; 20(7):496.
https://doi.org/10.3390/e20070496

**Chicago/Turabian Style**

Diósi, Lajos. 2018. "Fundamental Irreversibility: Planckian or Schrödinger–Newton?" *Entropy* 20, no. 7: 496.
https://doi.org/10.3390/e20070496