The shadow critical curves for different values of parameters.
The formation of cusp structures in the shadow critical curves at large angular momentum.
Shadow of Rotating Black Holes with Consistent Thermodynamics
Phys. Rev. D 113 (2026) 044044
Che-Yu Chen, Chiang-Mei Chen and Nobuyoshi Ohta
Shadow of Rotating Black Holes with Consistent Thermodynamics
我們研究具有尺度依賴牛頓常數的 Kerr 黑洞，並以熱力學一致性加以約束。結合 Sgr A* 的觀測資料，我們對模型參數空間給出限制，並指出黑洞陰影的特徵主要由事件視界性質所決定。值得注意的是，熱力學一致性預示陰影尺寸存在下限，且模型允許超越 Kerr 極限的自旋，並可能產生具有尖角結構的陰影。
We study Kerr black holes with a running Newton coupling, constrained by thermodynamic consistency. Using Sgr A* observations, we place bounds on the model and show that shadow features are largely determined by horizon properties. Notably, consistency implies a lower bound on shadow size and allows for possible super-Kerr rotation with distinctive cuspy shadows.