# Perturbative Accelerating Solutions of Relativistic Hydrodynamics

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## Abstract

**:**

## 1. Introduction

## 2. Perturbative Solutions of Hydrodynamics

## 3. Perturbations on Top of Hubble-Flow

- The scale variable S fulfills ${u}_{\mu}{\partial}^{\mu}S=0$ with the original flow field.

## 4. A Selected Sub-Class of Perturbative Solutions

## 5. Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

## References

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**Figure 1.**The perturbed flow field component (${u}_{x}+\delta {u}_{x}$) is shown in the left plot as a function of x, for $\tau =6$ fm/c (the other parameters are given in the text). The right plot indicates the relative change $({u}_{x}+\delta {u}_{x})/{u}_{x}$ for various $\delta $ and c values. The bottom plot shows the flow perturbation field $(\delta {u}_{x},\delta {u}_{y})$ in the transverse plane, for various proper-time values.

**Figure 2.**The perturbed pressure $p+\delta p$ is shown in the left plot as a function of x, for $\tau =6$ fm/c (the other parameters are given in the text). The right plot indicates the relative change $(p+\delta p)/p$ for various $\delta $ and c values. The bottom plot shows the pressure perturbation $\delta p$ in the transverse plane, for various proper-time values.

**Figure 3.**The perturbed density $n+\delta n$ is shown in the left plot as a function of x, for $\tau =6$ fm/c (the other parameters are given in the text). The right plot indicates the relative change $(n+\delta n)/n$ for various $\delta $ and c values.

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Kurgyis, B.; Csanád, M. Perturbative Accelerating Solutions of Relativistic Hydrodynamics. *Universe* **2017**, *3*, 84.
https://doi.org/10.3390/universe3040084

**AMA Style**

Kurgyis B, Csanád M. Perturbative Accelerating Solutions of Relativistic Hydrodynamics. *Universe*. 2017; 3(4):84.
https://doi.org/10.3390/universe3040084

**Chicago/Turabian Style**

Kurgyis, Bálint, and Máté Csanád. 2017. "Perturbative Accelerating Solutions of Relativistic Hydrodynamics" *Universe* 3, no. 4: 84.
https://doi.org/10.3390/universe3040084