https://doi.org/10.1140/epjc/s10052-026-15540-3
Regular Article - Theoretical Physics
Violation of cosmic censorship in Einstein–Maxwell-scalar models with fractional coupling
1
Physics Department, College of Physics and Optoelectronic Engineering, Jinan University, 510632, Guangzhou, China
2
Lanzhou Center for Theoretical Physics, Key Laboratory for Quantum Theory and Applications of the Ministry of Education, Key Laboratory of Theoretical Physics of Gansu Province, School of Physical Science and Technology, Lanzhou University, 730000, Lanzhou, China
3
Institute of Theoretical Physics, Research Center of Gravitation, School of Physical Science and Technology, Lanzhou University, 730000, Lanzhou, China
4
School of Physics, Nankai University, 300071, Tianjin, China
a
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Received:
29
December
2025
Accepted:
8
March
2026
Published online:
25
March
2026
Abstract
The weak cosmic censorship conjecture plays a foundational role in classical gravity by asserting that spacetime singularities are generically hidden behind event horizons. In this work, we explore its robustness in the Einstein–Maxwell-scalar theory with fractional coupling by studying both static black hole solutions and their fully nonlinear dynamical evolution. We identify a class of scalarized black holes that develop negative energy density near the event horizon, indicating violations of the classical energy conditions. Numerical evolutions of perturbed configurations reveal that sufficiently strong fractional coupling drives rapid curvature growth and geometric degeneration in the near-horizon region, accompanied by persistent negative energy density. While the simulations do not resolve the ultimate end state, the observed dynamics consistently point toward a weakening of the horizon-supporting structure and are suggestive of incipient naked singularity formation. These results uncover a classical mechanism through which fractional coupling can challenge the validity of the weak cosmic censorship conjecture in asymptotically flat spacetimes.
© The Author(s) 2026
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