New sources of ghost fields in k-essence theories for black-bounce solutions
C. F. S. Pereira, Denis C. Rodrigues, Ébano L. Martins, J. C. Fabris, Manuel E. Rodrigues
Abstract
Abstract In the present study, we generalize the possible ghost field configurations within the framework of k -essence theory to the Simpson–Visser metric area function <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msup> <mml:mi mathvariant="normal">Σ</mml:mi> <mml:mn>2</mml:mn> </mml:msup> <mml:mo>=</mml:mo> <mml:msup> <mml:mi>x</mml:mi> <mml:mn>2</mml:mn> </mml:msup> <mml:mo>+</mml:mo> <mml:msup> <mml:mi>a</mml:mi> <mml:mn>2</mml:mn> </mml:msup> </mml:mrow> </mml:math> . Our analysis encompasses field configurations for the region-defined metric function <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mi>A</mml:mi> <mml:mo>±</mml:mo> </mml:msub> </mml:mrow> </mml:math> as well as the general solution that asymptotically behaves as Schwarzschild-de Sitter for <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi>x</mml:mi> <mml:mo accent="false" stretchy="false">→</mml:mo> <mml:mo>−</mml:mo> <mml:mi mathvariant="normal">∞</mml:mi> </mml:mrow> </mml:math> . Specifically, we investigate two scalar field configurations and define the associated potential for each one. Through rigorous calculations, we verify that all equations of motion are satisfied. Notably, our findings indicate that even when proposing new configurations of ghost scalar fields, the energy conditions remain unchanged. This result serves to validate the wormhole solutions obtained in previous studies.