Krishnendu N V, Arun K G, Mishra Chandra Kant
Chennai Mathematical Institute, Siruseri 603103, India.
Indian Institute of Technology Madras, Chennai 600036, India.
Phys Rev Lett. 2017 Sep 1;119(9):091101. doi: 10.1103/PhysRevLett.119.091101. Epub 2017 Aug 31.
We propose a novel method to test the binary black hole nature of compact binaries detectable by gravitational wave (GW) interferometers and, hence, constrain the parameter space of other exotic compact objects. The spirit of the test lies in the "no-hair" conjecture for black holes where all properties of a Kerr black hole are characterized by its mass and spin. The method relies on observationally measuring the quadrupole moments of the compact binary constituents induced due to their spins. If the compact object is a Kerr black hole (BH), its quadrupole moment is expressible solely in terms of its mass and spin. Otherwise, the quadrupole moment can depend on additional parameters (such as the equation of state of the object). The higher order spin effects in phase and amplitude of a gravitational waveform, which explicitly contains the spin-induced quadrupole moments of compact objects, hence, uniquely encode the nature of the compact binary. Thus, we argue that an independent measurement of the spin-induced quadrupole moment of the compact binaries from GW observations can provide a unique way to distinguish binary BH systems from binaries consisting of exotic compact objects.
我们提出了一种新方法，用于测试引力波（GW）干涉仪可探测到的致密双星的双黑洞性质，从而限制其他奇异致密天体的参数空间。该测试的核心在于黑洞的“无毛”猜想，即克尔黑洞的所有性质都由其质量和自旋表征。该方法依赖于通过观测测量致密双星组分因其自旋而产生的四极矩。如果致密天体是克尔黑洞（BH），其四极矩仅可由其质量和自旋表示。否则，四极矩可能取决于其他参数（例如天体的状态方程）。引力波波形的相位和幅度中的高阶自旋效应明确包含致密天体的自旋诱导四极矩，因此唯一地编码了致密双星的性质。所以，我们认为通过引力波观测对致密双星的自旋诱导四极矩进行独立测量，可以提供一种独特的方法，将双黑洞系统与由奇异致密天体组成的双星区分开来。
