# On the Structure of the Vacuum in Quantum Gravity: A View from the Asymptotic Safety Scenario

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## Abstract

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## 1. Introduction

## 2. Higher-Derivative Scalar Theory

## 3. Kinetic Condensate in $\mathbf{R}+{\mathbf{R}}^{\mathbf{2}}$

## 4. Quadratic Gravity

## 5. Conclusions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**$f\left(r\right)$ (black) and $h\left(r\right)$ (red) obtained by solving the equations of motion of the quadratic theory as a function of the radial coordinate (in Planck units).

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**MDPI and ACS Style**

Bonanno, A.
On the Structure of the Vacuum in Quantum Gravity: A View from the Asymptotic Safety Scenario. *Universe* **2019**, *5*, 182.
https://doi.org/10.3390/universe5080182

**AMA Style**

Bonanno A.
On the Structure of the Vacuum in Quantum Gravity: A View from the Asymptotic Safety Scenario. *Universe*. 2019; 5(8):182.
https://doi.org/10.3390/universe5080182

**Chicago/Turabian Style**

Bonanno, Alfio.
2019. "On the Structure of the Vacuum in Quantum Gravity: A View from the Asymptotic Safety Scenario" *Universe* 5, no. 8: 182.
https://doi.org/10.3390/universe5080182