论文标题
了解在渐近极限的角度Teukolsky方程的解决方案
Understanding solutions of the angular Teukolsky equation in the prolate asymptotic limit
论文作者
论文摘要
Angular Teukolsky方程的解决方案已用于解决物理学中的各种应用问题,对于黑洞物理学非常重要,尤其是在计算准模式和极端质量的灵感问题中。该方程式的本征函数,称为自旋加权球函数,基本上是自旋加权球形谐波和标量球形谐波的概括。虽然后者的函数在分析上得到了很好的理解,但自旋加权球体谐波仅在球形和扁渐进限制中在分析上以分析为单位。在渐造渐近极限中理解它们的尝试取得了有限的成功。在这里,我们利用高准确的数值溶液方案来广泛探索可能的倾斜溶液的空间,并为渐近渐近限制的特征值提取分析渐近扩展。令人惊讶的是,我们发现两类的渐近行为。一个类(称为“正常”)的行为与先前的工作中分析得出的领先行为一致。以前没有预测第二类溶液,但是该类别的解决方案是导致在过渡到渐近行为期间先前数值溶液中所见的无法解释的行为。在这种“异常”类中,解决方案的行为比正常类中的溶液的行为更为复杂,基于不同渐近顺序的特征值的行为,异常类别分为不同的类型。我们探讨了何时出现异常解决方案并发现必要的问题,但没有足够的条件来生存。我们希望对Prate解决方案进行广泛的数值研究将激发并为这些重要功能提供新的分析研究。
Solutions to the Angular Teukolsky Equation have been used to solve various applied problems in physics and are extremely important to black-hole physics, particularly in computing quasinormal modes and in the extreme-mass-ratio inspiral problem. The eigenfunctions of this equation, known as spin-weighted spheroidal functions, are essentially generalizations of both the spin-weighted spherical harmonics and the scalar spheroidal harmonics. While the latter functions are quite well understood analytically, the spin-weighted spheroidal harmonics are only known analytically in the spherical and oblate asymptotic limits. Attempts to understand them in the prolate asymptotic limit have met limited success. Here, we make use of a high-accuracy numerical solution scheme to extensively explore the space of possible prolate solutions and extract analytic asymptotic expansions for the eigenvalues in the prolate asymptotic limit. Somewhat surprisingly, we find two classes of asymptotic behavior. The behavior of one class, referred to as "normal", is in agreement with the leading-order behavior derived analytically in prior work. The second class of solutions was not previously predicted, but solutions in this class are responsible for unexplained behavior seen in previous numerical prolate solutions during the transition to asymptotic behavior. The behavior of solutions in this "anomalous" class is more complicated than that of solutions in the normal class, with the anomalous class separating into different types based on the behavior of the eigenvalues at different asymptotic orders. We explore the question of when anomalous solutions appear and find necessary, but not sufficient conditions for their existence. It is our hope that this extensive numerical investigation of the prolate solutions will inspire and inform new analytic investigations into these important functions.