# Effective Hamiltonians in Nonrelativistic Quantum Electrodynamics

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## Abstract

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## 1. Introduction

## 2. The General Expression of the Effective Hamiltonian in Molecular Quantum Electrodynamics

## 3. Diagonal and Off-Diagonal Matrix Elements of the Effective Hamiltonian

#### 3.1. Diagonal Elements of the Effective Hamiltonian and Ground-State Systems (Zero Photons)

#### 3.2. Off-Diagonal Elements of the Effective Hamiltonian

## 4. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

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**MDPI and ACS Style**

Passante, R.; Rizzuto, L.
Effective Hamiltonians in Nonrelativistic Quantum Electrodynamics. *Symmetry* **2021**, *13*, 2375.
https://doi.org/10.3390/sym13122375

**AMA Style**

Passante R, Rizzuto L.
Effective Hamiltonians in Nonrelativistic Quantum Electrodynamics. *Symmetry*. 2021; 13(12):2375.
https://doi.org/10.3390/sym13122375

**Chicago/Turabian Style**

Passante, Roberto, and Lucia Rizzuto.
2021. "Effective Hamiltonians in Nonrelativistic Quantum Electrodynamics" *Symmetry* 13, no. 12: 2375.
https://doi.org/10.3390/sym13122375