English

Simple method to generate magnetically charged ultra-static traversable wormholes without exotic matter in Einstein-scalar-Gauss-Bonnet gravity

General Relativity and Quantum Cosmology 2024-01-01 v2

Abstract

All the magnetically charged ultrastatic and spherically symmetric spacetime solutions in the framework of linear/nonlinear electrodynamics, with an arbitrary electromagnetic Lagrangian density L(F)\mathcal{L}(\mathcal{F}) depending only of the electromagnetic invariant F ⁣= ⁣FαβFαβ ⁣/4\mathcal{F}\!=\!F_{\alpha\beta}F^{\alpha\beta}\!/4, minimally coupled to Einstein-scalar-Gauss-Bonnet gravity [EsGB-L(F)\mathcal{L}(\mathcal{F})], are found. We also show that a magnetically charged ultrastatic and spherically symmetric EsGB-L(F)\mathcal{L}(\mathcal{F}) solution with invariant F\mathcal{F} having a strict global maximum value F0\mathcal{F}_{_{0}} in the entire domain of the solution, and such that L0=L(F0)>0\mathcal{L}_{_{0}}=\mathcal{L}(\mathcal{F}_{_{0}})>0, can be interpreted as an ultrastatic wormhole spacetime geometry with throat radius determined by the scalar charge and the quantity L0\mathcal{L}_{_{0}}. We provide some examples, including Maxwell's theory of electrodynamics (linear electrodynamics) LLED ⁣= ⁣F\mathcal{L}_{_{_{\mathrm{LED}}}} \!=\! \mathcal{F}, producing the magnetic dual of the purely electric Ellis-Bronnikov EsGB Maxwell wormhole derived in [P. Ca\~nate, J. Sultana, D. Kazanas, Phys. Rev. D {\bf100}, 064007 (2019)]; and the nonlinear electrodynamics (NLED) models given by Born-Infeld LBI ⁣= ⁣4β2+4β21+F ⁣/ ⁣(2β2) \mathcal{L}_{_{_{\mathrm{BI}}}} \!=\! -4\beta^{2} + 4\beta^{2} \sqrt{ 1 + \mathcal{F}\!/\!(2\beta^{2})~}, and Euler-Heisenberg in the approximation of the weak-field limit LEH ⁣= ⁣LLED+γF2 ⁣/2\mathcal{L}_{_{_{\mathrm{EH}}}} \!=\! \mathcal{L}_{_{_{\mathrm{LED}}}} + \gamma \mathcal{F}^{2}\!/2. With those NLED models, two novel magnetically charged ultrastatic traversable wormholes (EsGB Born-Infeld and EsGB Euler-Heisenberg wormholes) are presented as exact solutions without exotic matter in EsGB-L(F)\mathcal{L}(\mathcal{F}) gravity.

Keywords

Cite

@article{arxiv.2310.08758,
  title  = {Simple method to generate magnetically charged ultra-static traversable wormholes without exotic matter in Einstein-scalar-Gauss-Bonnet gravity},
  author = {Pedro Cañate},
  journal= {arXiv preprint arXiv:2310.08758},
  year   = {2024}
}

Comments

Typos corrected