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arXiv · 0907.1189

Brane Gravitational Extension of Dirac's "Extensible Model of the Electron"

Aharon Davidson·Shimon Rubin
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Abstract

A gravitational extension of Dirac's "Extensible model of the electron" is presented. The Dirac bubble, treated as a 3-dim electrically charged brane, is dynamically embedded within a 4-dim $Z_{2}$-symmetric Reissner-Nordstrom bulk. Crucial to our analysis is the gravitational extension of Dirac's brane variation prescription; its major effect is to induce a novel geometrically originated contribution to the energy-momentum tensor on the brane. In turn, the effective potential which governs the evolution of the bubble exhibits a global minimum, such that the size of the bubble stays finite (Planck scale) even at the limit where the mass approaches zero. This way, without fine-tuning, one avoids the problem so-called 'classical radius of the electron'.

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Aharon Davidson, Shimon Rubin. 2009-10-13. Brane Gravitational Extension of Dirac's "Extensible Model of the Electron". https://doi.org/10.1088/0264-9381%2F26%2F23%2F235006

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