# Quantum Entanglement in the Multiverse

^{1}

^{2}

## Abstract

**:**

## 1. Introduction

## 2. Entangled States

## 3. Initially Entangled State and Its Spectrum

#### 3.1. Initially Entangled State

#### 3.2. Density Matrix

#### 3.3. Spectrum

## 4. Initially Non-Entangled State and Its Spectrum

#### 4.1. Initially Non-Entangled State

#### 4.2. Spectrum

## 5. Entangled and Non-Entangled States with Two-Particle Discrepancy

## 6. Summary

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Causal diagram of the inflationary multiverse. We suppose that our universe is BD2 and BD1 is our partner universe. The electrons of spin-up and down are just for visualization in order to clearly see that a pair of entangled universe was nucleated.

**Figure 2.**Plots of enhanced spectrum (orange) as the effect of the entanglement ($\mathcal{C}=1/\sqrt{2}$), and a standard Bunch-Davies flat spectrum (blue) ($\mathcal{C}=1$) for comparison.

**Figure 3.**Plots of an oscillatory spectrum (green) and bi-frequency modulation (orange) as the effect of the quantum interference, and a standard flat spectrum (blue) for comparison. Note that these oscillations are artificial in order to visualize the effect of the quantum interference.

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**MDPI and ACS Style**

Kanno, S.
Quantum Entanglement in the Multiverse. *Universe* **2017**, *3*, 28.
https://doi.org/10.3390/universe3020028

**AMA Style**

Kanno S.
Quantum Entanglement in the Multiverse. *Universe*. 2017; 3(2):28.
https://doi.org/10.3390/universe3020028

**Chicago/Turabian Style**

Kanno, Sugumi.
2017. "Quantum Entanglement in the Multiverse" *Universe* 3, no. 2: 28.
https://doi.org/10.3390/universe3020028