# The Definition of Entropy for Quantum Unstable Systems: A View-Point Based on the Properties of Gamow States

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## Abstract

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## 1. Introduction

## 2. Entropy and time Evolution

## 3. Resonances in Quantum Systems

## 4. Complex Entropy

## 5. Time-Temperature Plane

## 6. Final Remarks

## Acknowledgments

## Author Contributions

## Conflicts of Interest

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**MDPI and ACS Style**

Civitarese, O.; Gadella, M. The Definition of Entropy for Quantum Unstable Systems: A View-Point Based on the Properties of Gamow States. *Entropy* **2018**, *20*, 231.
https://doi.org/10.3390/e20040231

**AMA Style**

Civitarese O, Gadella M. The Definition of Entropy for Quantum Unstable Systems: A View-Point Based on the Properties of Gamow States. *Entropy*. 2018; 20(4):231.
https://doi.org/10.3390/e20040231

**Chicago/Turabian Style**

Civitarese, Osvaldo, and Manuel Gadella. 2018. "The Definition of Entropy for Quantum Unstable Systems: A View-Point Based on the Properties of Gamow States" *Entropy* 20, no. 4: 231.
https://doi.org/10.3390/e20040231