# Observational Consequences of an Interacting Multiverse

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## Abstract

**:**

## 1. Introduction

## 2. Interacting Multiverse

#### 2.1. Quantum Multiverse

#### 2.2. Interacting Scheme

#### 2.3. Modified Properties

## 3. Observational Imprints

## 4. Conclusions

## Acknowledgments

## Conflicts of Interest

## References

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1 | Let us add the superscript 3 to the action, the Lagrangian and to the Hamiltonian density of the third quantization procedure. |

2 | To our knowledge, this was first done in Ref. [2]. Before that, the multiverse was considered by many physicists to be an exotic proposal deprived of any scientific validation. Still today, there are many scientists that are sceptic about the whole proposal. However, we can now pose new and more precise observable imprints, and more and more groups are working on the search of the imprints of the multiverse [2,3,13,14,15,16,17,18,19,20]. |

**Figure 1.**The effect of the interaction among universe with a Coleman-DeLucia potential (

**left**) and with a quartic potential (

**right**). Ref. [9]

**Figure 2.**Landscape structure for plateau like potentials. The potential energy of the plateau can be large enough to trigger inflation for a high value of the mode n. Afterwards, the universe may undergo a series of vacuum decays [9].

**Figure 3.**The departure of different pre-inflationary stages from the exponential DeSitter evolution of the universe (red): matter-dominated evolution (blue), radiation-dominated evolution (green), and the evolution dominated by the quantum corrections induced by the interactions between universes (black). Ref. [9]

**Figure 4.**Suppression of the lowest modes of the power spectrum of the CMB induced by the existence of a pre-inflationary stage of the universe dominated by: (i) a network of frustrated domain walls (dotted blue line); and (ii) a network of frustrated cosmic strings (dashed red line). Picture elaborated from the original figures of Ref. [12].

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**MDPI and ACS Style**

Robles-Pérez, S.J.
Observational Consequences of an Interacting Multiverse. *Universe* **2017**, *3*, 49.
https://doi.org/10.3390/universe3020049

**AMA Style**

Robles-Pérez SJ.
Observational Consequences of an Interacting Multiverse. *Universe*. 2017; 3(2):49.
https://doi.org/10.3390/universe3020049

**Chicago/Turabian Style**

Robles-Pérez, Salvador J.
2017. "Observational Consequences of an Interacting Multiverse" *Universe* 3, no. 2: 49.
https://doi.org/10.3390/universe3020049