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arXiv · 2606.03263

Thermodynamical phase structures and particle emission rate of charged AdS black hole surrounded by string cloud and quintessence via shadow formalism

Yunxiang Wang·Hongyu Chen·Juhua Chen·Yongjiu Wang
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Abstract

In this paper, the shadow of the four-dimensional charged AdS black hole surrounded by string cloud and quintessence is derived. The shadow radius shows a strictly monotonic and invertible correlation with the event horizon radius. The phase structures of the black hole for different parameters are reproduced through traditional thermodynamic geometry, which are similar to a van der Waals system. By analyzing the phase structure of the black hole in the context of shadows, thermodynamical phase structures with the shadow radius as the variable replicate the phase transition with the event horizon radius as the variable. We present the energy emission rates for massless and massive particles and discover that the maximum emission frequency can also serve as a useful tool for thermodynamic analysis. We firstly study and systematically establish shadow thermodynamics under the background of string cloud and quintessence, and our results reveal the independent regulatory mechanism of dark components on phase transitions as well as the universal topological invariance of the phase transition structure.

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Yunxiang Wang, Hongyu Chen, Juhua Chen, Yongjiu Wang. 2026-06-02. Thermodynamical phase structures and particle emission rate of charged AdS black hole surrounded by string cloud and quintessence via shadow formalism. https://arxiv.org/abs/2606.03263

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