The pure R 2 gravity is equivalent to Einstein gravity with cosmological constant and a massless scalar field, and it further possesses the so-called restricted Weyl symmetry, which is a symmetry larger than scale symmetry. To incorporate matter, we consider a restricted Weyl invariant action composed of pure R 2 gravity, SU(2) Yang-Mills fields, and a nonminimally coupled massless Higgs field (a triplet of scalars). When the restricted Weyl symmetry is spontaneously broken, it is equivalent to an Einstein-Yang-Mills-Higgs (EYMH) action with a cosmological constant and a massive Higgs nonminimally coupled to gravity, i.e., via a term ξ ? R | Φ → | 2 . When the restricted Weyl symmetry is not spontaneously broken, linearizations about Minkowski spacetime do not yield gravitons in the original R 2 gravity and hence it does not gravitate. However, we show that in the broken gauge sector of our theory, where the Higgs field acquires a nonzero vacuum expectation value, Minkowski spacetime is a viable gravitating background solution. We then obtain numerically gravitating magnetic monopole solutions for nonzero coupling constant ξ ? = 1 / 6 in three different backgrounds: Minkowski, anti–de Sitter (AdS), and de Sitter (dS), all of which are realized in our restricted Weyl invariant theory.
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