#
Exponential Cosmological Solutions with Three Different Hubble-Like Parameters in (1 + 3 + k_{1} + k_{2})-Dimensional EGB Model with a Λ-Term

^{1}

^{2}

^{*}

## Abstract

**:**

## 1. Introduction

**Remark**

**1.**

## 2. The Cosmological Model

## 3. The Case ${\mathbf{k}}_{\mathbf{1}}\ne {\mathbf{k}}_{\mathbf{2}}$

#### Extremum Points

**Proposition**

**1.**

## 4. The Case ${\mathbf{k}}_{\mathbf{1}}={\mathbf{k}}_{\mathbf{2}}$

**Proposition**

**2.**

## 5. The Analysis of Stability

**Proposition**

**3.**

**Proposition**

**4.**

## 6. Solutions Corresponding to Zero Variation of $\mathit{G}$

## 7. Conclusions and Discussion

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## Appendix A

**Lemma**

**A1.**

**Proof.**

**Lemma**

**A2.**

**Proof.**

**Lemma**

**A3.**

**Proof.**

**Lemma**

**A4.**

**Proof.**

**Lemma**

**A5.**

**Proof.**

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**MDPI and ACS Style**

Ernazarov, K.K.; Ivashchuk, V.D.
Exponential Cosmological Solutions with Three Different Hubble-Like Parameters in (1 + 3 + *k*_{1} + *k*_{2})-Dimensional EGB Model with a Λ-Term. *Symmetry* **2020**, *12*, 250.
https://doi.org/10.3390/sym12020250

**AMA Style**

Ernazarov KK, Ivashchuk VD.
Exponential Cosmological Solutions with Three Different Hubble-Like Parameters in (1 + 3 + *k*_{1} + *k*_{2})-Dimensional EGB Model with a Λ-Term. *Symmetry*. 2020; 12(2):250.
https://doi.org/10.3390/sym12020250

**Chicago/Turabian Style**

Ernazarov, K. K., and V. D. Ivashchuk.
2020. "Exponential Cosmological Solutions with Three Different Hubble-Like Parameters in (1 + 3 + *k*_{1} + *k*_{2})-Dimensional EGB Model with a Λ-Term" *Symmetry* 12, no. 2: 250.
https://doi.org/10.3390/sym12020250