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arXiv · 2203.05720

Braneworlds in $f(Q)$ gravity

J. E. G. Silva·R. V. Maluf·Gonzalo J. Olmo·C. A. S. Almeida
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Abstract

We propose a braneworld scenario in a modified symmetric teleparallel gravitational theory, where the dynamics for the gravitational field is encoded in the nonmetricity tensor rather than in the curvature. Assuming a single real scalar field with a sine-Gordon self-interaction, the generalized quadratic nonmetricity invariant $\mathbb{Q}$ controls the brane width while keeping the shape of the energy density. By considering power corrections of the invariant $\mathbb{Q}$ in the gravitational Lagrangian, the sine-Gordon potential is modified exhibiting new barriers and false vacuum. As a result, the domain wall brane obtains an inner structure, and it undergoes a splitting process. In addition, we also propose a non-minimal coupling between a bulk fermion field and the nonmetricity invariant $\mathbb{Q}$. Such geometric coupling leads to a massless chiral fermion bound to the 3-brane and a stable tower of non-localized massive states.

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J. E. G. Silva, R. V. Maluf, Gonzalo J. Olmo, C. A. S. Almeida. 2022-03-11. Braneworlds in $f(Q)$ gravity. https://doi.org/10.1103/physrevd.106.024033

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