https://doi.org/10.1140/epjc/s10052-023-12144-z
Regular Article - Theoretical Physics
Nonlinear instability and scalar clouds of spherical exotic compact objects in scalar-Gauss-Bonnet theory
1
Institute for Theoretical Physics and Cosmology, Zhejiang University of Technology, 310032, Hangzhou, China
2
United Center for Gravitational Wave Physics, Zhejiang University of Technology, 310032, Hangzhou, China
Received:
10
September
2023
Accepted:
12
October
2023
Published online:
21
October
2023
In this work, we present a new type of scalar clouds supported by spherically symmetric horizonless compact objects in the scalar-Gauss–Bonnet theory. Unlike the previous spontaneous scalarization that is triggered by the tachyonic instability, our scalarization arises from a nonlinear instability that is non-spontaneous. We explore two types of boundary conditions for the scalar field at the surface of the compact objects and find an infinite countable set of scalar clouds characterized by the number of nodes for both cases. Our study demonstrates that boundary conditions have a significant impact on the formation of scalar clouds. Specifically, for the Dirichlet boundary condition, scalarization is more likely to occur for compact objects with medium radii and becomes harder for ultra-compact and large ones. Conversely, for the Robin boundary condition, scalarization is easier for more compact objects.
© The Author(s) 2023
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Funded by SCOAP3. SCOAP3 supports the goals of the International Year of Basic Sciences for Sustainable Development.