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Self-gravitating stringlike configurations from nonlinear electodynamics

K. A. Bronnikov·G. N. Shikin·E. N. Sibileva
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Abstract

We consider static, cylindrically symmetric configurations in general relativity coupled to nonlinear electrodynamics (NED) with an arbitrary gauge-invariant Lagrangian of the form $L_{em}= Φ(F)$, $F =F_{mn}F^{mn}$. We study electric and magnetic fields with three possible orientations: radial (R), longitudinal (L) and azimuthal (A), and try to find solitonic stringlike solutions, having a regular axis and a flat metric at large $r$, with a possible angular defect. Assuming the function $Φ(F)$ to be regular at small $F$, it is shown that a regular axis is impossible in R-fields if there is a nonzero effective electric charge and in A-fields if there is a nonzero effective electric current along the axis. Solitonic solutions are only possible for purely magnetic R-fields and purely electric A-fields, in cases when $Φ(F)$ tends to a finite limit at large $F$. For both R- and A-fields, the desired large $r$ asymptotic is only possible with a non- Maxwell behaviour of $Φ(F)$ at small $F$. For L-fields, solutions with a regular axis are easily obtained (and can be found by quadratures) whereas a desired large $r$ asymptotic is only possible in an exceptional solution; the latter gives rise to solitonic configurations in case $Φ(F) = \const \cdot \sqrt{F}$. We give an explicit example of such a solution.

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K. A. Bronnikov, G. N. Shikin, E. N. Sibileva. 2003-08-01. Self-gravitating stringlike configurations from nonlinear electodynamics. https://doi.org/10.1023/b%3Agerg.0000032146.03936.45

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