Goldstone's Theorem and Hamiltonian of Multi-galileon Modified Gravity

TL;DR

This paper explores symmetry breaking in multi-galileon modified gravity models, applying a modified Goldstone's theorem and deriving the Hamiltonian to understand their fundamental properties.

Contribution

It introduces a modified Goldstone's theorem for multi-galileon theories and derives the Hamiltonian, advancing theoretical understanding of these modified gravity models.

Findings

Modified Goldstone's theorem applicable to multi-galileon symmetry breaking

Derived Hamiltonian for general multi-galileon theories

Insights into the stability and dynamics of self-accelerating solutions

Abstract

The galileon model was recently proposed to locally describe a class of modified gravity theories, including the braneworld DGP model. We discuss spontaneous symmetry breaking of the self-accelerating branch in a multi-galileon theory with internal global symmetries. We show a modified version of Goldstone's theorem is applicable to the symmetry breaking pattern and discuss its implications. We also derive the Hamiltonian of a general multi-galileon theory and discuss its implications.