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تسجيل مستخدم جديدStability analysis of black holes by the $S$-deformation method for coupled systems
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We propose a simple method to prove the linear mode stability of a black hole when the perturbed field equations take the form of a system of coupled Schrodinger equations. The linear mode stability of the spacetime is guaranteed by the existence of an appropriate $S$-deformation. Such an $S$-deformation is related to the Riccati transformation of a solution to the Schrodinger system with zero energy. We apply this formalism to some examples and numerically study their stability.
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The $S$-deformation method is a useful way to show the linear mode stability of a black hole when the perturbed field equation takes the form of the Schrodinger equation. While previous works where many explicit examples are studied suggest that this
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