arXiv:2409.04458v1 Announce Type: new
Abstract: Recent studies have demonstrated that a scalar field non-minimally coupled to the electromagnetic field can experience a spin-induced tachyonic instability near Kerr-Newman black holes, potentially driving the formation of scalar clouds. In this paper, we construct such scalar clouds for both fundamental and excited modes, detailing their existence domains and wave functions. Our results indicate that a sufficiently strong coupling between the scalar and electromagnetic fields is essential for sustaining scalar clouds. Within the strong coupling regime, black holes that rotate either too slowly or too rapidly are unable to support scalar clouds. Furthermore, we observe that scalar cloud wave functions are concentrated near the black hole’s poles. These findings provide a foundation for future investigations of spin-induced scalarized Kerr-Newman black holes.
Spin-induced Scalarized Kerr-Newman Black Holes: Insights and Future Directions
Recent studies have revealed the existence of a spin-induced tachyonic instability near Kerr-Newman black holes, which can give rise to the formation of scalar clouds. In this paper, we investigate the properties of these scalar clouds and their dependence on the coupling between the scalar and electromagnetic fields. Our findings shed light on the conditions required for the formation and sustenance of such clouds.
Key Conclusions:
- Scalar clouds can form around Kerr-Newman black holes due to the spin-induced tachyonic instability.
- The strength of the coupling between the scalar and electromagnetic fields greatly influences the existence and characteristics of the scalar clouds.
- Black holes with slow or rapid rotation do not support sustained scalar clouds.
- The wave functions of scalar clouds are concentrated near the poles of the black hole.
Roadmap for Future Research:
The insights gained from this study open up various avenues for future investigation and exploration. Some potential challenges and opportunities can be identified:
- 1. Exploring different coupling strengths: Further analysis is needed to understand the effect of different coupling strengths on the formation and stability of scalar clouds. The dependence of the clouds’ characteristics on the strength of the coupling can provide valuable insights into the underlying physics.
- 2. Probing the behavior of scalar clouds around different black hole configurations: Investigating scalar clouds around different types of black holes, such as rotating and charged black holes, can help uncover how the presence of additional parameters influences their existence and properties. This wider exploration will contribute to a comprehensive understanding of scalarized black holes.
- 3. Extending the study to higher dimensions: Extending the analysis to higher-dimensional scenarios can provide insights into the behavior and properties of scalar clouds in higher-dimensional black hole spacetimes. This extension may uncover new phenomena and shed light on the nature of scalarized black holes in higher dimensions.
- 4. Investigating the impact of scalar clouds on the black hole’s environment: Understanding the interaction between scalar clouds and the surrounding environment, including accretion disks and other matter, can yield valuable information about the influence of scalarized black holes on their surroundings. This investigation may have implications for astrophysical observations and could explain certain phenomena associated with active galactic nuclei.
The future roadmap outlined above presents exciting opportunities for further research in the field of spin-induced scalarized Kerr-Newman black holes. Advancements in these directions will deepen our understanding of the behavior and implications of scalar clouds, and their role in the dynamics of black hole systems.