# Revisiting the Cosmological Constant Problem within Quantum Cosmology

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## Abstract

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## 1. Introduction

## 2. The Three Main Model Groups and the Seven Principal Model Categories

## 3. Cosmological Constant within Quantum Cosmology

## 4. Multiverse Partition Function and the Typical Size of a General $\zeta $-Universe

## 5. Discussions and Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

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1. | The negative sign is for consistency of moving $\Lambda $ from the RHS to the LHS of the equation, as well as for convenience in relating $\Lambda $ to the scalar curvature R. |

2. | The ratio is even smaller ($\sigma /\rho =5/4=1.25$) if one is to consider equal energy partition per degree of freedom ($1/2$) with dimension degree of freedom n deduced from the scaling $\rho \sim {r}^{-n}$. |

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Gueorguiev, V.G.; Maeder, A. Revisiting the Cosmological Constant Problem within Quantum Cosmology. *Universe* **2020**, *6*, 108.
https://doi.org/10.3390/universe6080108

**AMA Style**

Gueorguiev VG, Maeder A. Revisiting the Cosmological Constant Problem within Quantum Cosmology. *Universe*. 2020; 6(8):108.
https://doi.org/10.3390/universe6080108

**Chicago/Turabian Style**

Gueorguiev, Vesselin G., and Andre Maeder. 2020. "Revisiting the Cosmological Constant Problem within Quantum Cosmology" *Universe* 6, no. 8: 108.
https://doi.org/10.3390/universe6080108