# Unruh Effect and Information Entropy Approach

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## Abstract

**:**

## 1. Introduction

## 2. Probability and Entropy

## 3. Unruh Effect

## 4. Unruh Entropy

- In order to obey, the energy conservation law N should be finite;
- In the case of (2 + 1) or (3 + 1)-dimensional space-time, the Unruh horizon should be considered as a radiation source of finite size.

## 5. Asymptotics of Unruh Entropy

## 6. Generalization to Intrinsic Degrees of Freedom

## 7. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

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**Figure 1.**(Color online) The entropy $H(n,E|N,T)$ of Unruh radiation given by Equation (17) for fermions $(N=2)$ as function of $m/T$ and $M/T$.

**Figure 2.**(Color online) The same as Figure 1 but for bosons. The spectrum of bosons contains (

**a**) $N=100$ and (

**b**) $N=1000$ particles.

**Figure 3.**(Color online) Asymptotic behavior of entropy $H(n,E|N,T)$ given by Equation (23) at $T\to 0$ as function of $m/T$.

**Figure 4.**(Color online) High-temperature asymptotics of the entropy $H(n,E|N,T)$ of Unruh radiation given by Equation (28) for fermions $(N=2)$ as a function of m and M.

**Figure 5.**(Color online) The same as Figure 4 but for bosons with (

**a**) $N=100$ and (

**b**) $N=1000$ particles in the spectrum.

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Teslyk, M.; Bravina, L.; Zabrodin, E.
Unruh Effect and Information Entropy Approach. *Particles* **2022**, *5*, 157-170.
https://doi.org/10.3390/particles5020014

**AMA Style**

Teslyk M, Bravina L, Zabrodin E.
Unruh Effect and Information Entropy Approach. *Particles*. 2022; 5(2):157-170.
https://doi.org/10.3390/particles5020014

**Chicago/Turabian Style**

Teslyk, Maksym, Larissa Bravina, and Evgeny Zabrodin.
2022. "Unruh Effect and Information Entropy Approach" *Particles* 5, no. 2: 157-170.
https://doi.org/10.3390/particles5020014