用快子物质解冻玻恩-因费尔德双荷冻结星：振荡谱
Defrosting the Born-Infeld dyonic frozen star with tachyon matter: spectrum of oscillations
AI总结：
研究用快子物质解冻玻恩 - 因费尔德双荷冻结星的振荡谱，通过玻恩 - 因费尔德拉格朗日量以更简单方式得到谱，验证声速与γ、寿命与1/γ²的关系，保证了扰动方程一致性，利于对远离平衡的冻结星做数值研究。
AI中文摘要：
冻结星是天体物理黑洞内部的一种模型，外部与史瓦西黑洞奇异几何无法区分，但其无奇点和俘获面。它对应宏观‘BIon’，是耦合爱因斯坦引力的特定玻恩 - 因费尔德拉格朗日量的解。通量管的刚性使其在几何和物质线性扰动下超稳定。加入微扰磁单极子电荷和快子动能可使星‘解冻’产生内部脉动，成为宏观‘DIon’。此前通过将能量 - 动量张量视为流体，对解冻星非径向振荡进行微扰分析，本文用玻恩 - 因费尔德拉格朗日量以更简单方式得到相同谱，验证声速与γ成正比，参数化长寿命与1/γ²成正比，且因扰动方程由拉格朗日量导出，保证了任意偏离球对称时的一致性，便于对远离平衡的冻结星进行数值研究。
英文摘要：
The frozen star is a model for the interior of an astrophysical black hole that is externally indistinguishable from the singular geometry of a Schwarzschild black hole, even though it contains no singularities nor trapped surfaces. The frozen star corresponds to a macroscopic ``BIon'', a solution of a certain type of Born-Infeld Lagrangian coupled to Einstein gravity, which consists of rigid flux tubes sourced by an electric charge localized at its center and a uniform distribution of opposite charge along its outer surface. This configuration is a solution of the effective action that describes the end point of tachyon condensation in string. The rigidity of the flux tubes implies that the star is ultrastable under linear perturbations of the geometry and matter. The star can be effectively deformed, or ``defrosted'', allowing internal pulsations, as expected from regular, horizonless astrophysical black holes. To describe the defrosted star, we need to include a perturbative amount of magnetic-monopole charge and tachyon kinetic energy. This recasts the star as a macroscopic ``DIon'', whose flux tubes can stretch and contract, having both electric and magnetic charges localized at its center and distributed uniformly along its outer surface. Previously, the non-radial oscillations of the defrosted star were analyzed to leading order in a perturbative ``defrosting'' parameter $γ$, by describing the energy-momentum tensor as that of a fluid. Here, we derive the same spectrum in a much simpler way, using the Born-Infeld Lagrangian. Thus, we verify that the sound velocities scale as $γ$ and the parametrically long lifetimes scale as $1/γ^2$. Because the perturbation equations are derived from a Lagrangian, their consistency is guaranteed for arbitrary deviations away from spherical symmetry, facilitating numerical studies on frozen stars away from equilibrium.
