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arXiv · hep-ph/0003145

The (in)stability of global monopoles revisited

Ana Achucarro·Jon Urrestilla
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Abstract

We analyse the stability of global O(3) monopoles in the infinite cut-off (or scalar mass) limit. We obtain the perturbation equations and prove that the spherically symmetric solution is classically stable (or neutrally stable) to axially symmetric square integrable or power-law decay perturbations. Moreover we show that, in spite of the existence of a conserved topological charge, the energy barrier between the monopole and the vacuum is finite even in the limit where the cut-off is taken to infinity. This feature is specific of global monopoles and independent of the details of the scalar potential.

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Ana Achucarro, Jon Urrestilla. 2000-07-25. The (in)stability of global monopoles revisited. https://doi.org/10.1103/physrevlett.85.3091

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