Testing general relativity with black hole-pulsar binaries
Testing general relativity with black hole-pulsar binaries
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DOI：
10.1103/physrevd.98.124007
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发表时间：
2018-08
影响因子：
5
通讯作者：
Brian C Seymour;Kent Yagi
中科院分区：
文献类型：
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作者：
Brian C Seymour;Kent Yagi
双星使我们能够对引力进行精确的测试，并对广义相对论之外的广泛理论施加了严格的限制。目前和未来的射电望远镜，如FAST、SKA和MeerKAT，可能会发现一个新的天体物理系统，即围绕黑洞运行的脉冲星，这将为我们探测引力提供新的来源。在本文中，我们系统地研究了利用这类黑洞脉冲星双星检验广义相对论的前景。我们开始通过寻找一个映射之间的一般非爱因斯坦参数的轨道衰减率和理论常数在各种修改的引力理论，然后总结这个映射与一个现成的使用列表。我们在这里研究的理论包括标量张量理论，变G理论，大质量引力理论，通用屏蔽引力和二次曲率校正理论。接下来，我们使用模拟测量精度的黑洞脉冲星双星的轨道衰减率与FAST/SKA，并推导出上述通用的非爱因斯坦参数的投影上界。我们发现，这样的边界从黑洞-脉冲星可以强于中子星脉冲星和中子星白矮星双星的几个数量级时，进入负后牛顿订单的校正。通过映射这些边界上的通用参数的各种修改后的引力理论，我们发现，一个可以约束的时间变化量牛顿常数$G$的可比性或略弱于目前最强的约束从太阳系实验，虽然前者的边界是互补的，后者，因为它们探测不同的重力制度。我们还研究了如何从黑洞四极矩测量的黑洞-黑洞引力探测二次引力。我们发现，宇称违反部门的二次引力的界限可以比目前的界限强六个数量级。这些结果表明，未来新发现的黑洞将为进一步探测引力提供强有力的方法。
Binary pulsars allow us to carry out precision tests of gravity and have placed stringent bounds on a broad class of theories beyond general relativity. Current and future radio telescopes, such as FAST, SKA, and MeerKAT, may find a new astrophysical system, a pulsar orbiting around a black hole, which will provide us a new source for probing gravity. In this paper, we systematically study the prospects of testing general relativity with such black hole-pulsar binaries. We begin by finding a mapping between generic non-Einsteinian parameters in the orbital decay rate and theoretical constants in various modified theories of gravity and then summarize this mapping with a ready-to-use list. Theories we study here include scalar-tensor theories, varying $G$ theories, massive gravity theories, generic screening gravity and quadratic curvature-corrected theories. We next use simulated measurement accuracy of the orbital decay rate for black hole-pulsar binaries with FAST/SKA and derive projected upper bounds on the above generic non-Einsteinian parameters. We find that such bounds from black hole-pulsars can be stronger than those from neutron star-pulsar and neutron star-white dwarf binaries by a few orders of magnitude when the correction enters at negative post-Newtonian orders. By mapping such bounds on generic parameters to those on various modified theories of gravity, we find that one can constrain the amount of time variation in Newton's constant $G$ to be comparable to or slightly weaker than the current strongest bound from solar system experiments, though the former bounds are complementary to the latter since they probe different regime of gravity. We also study how well one can probe quadratic gravity from black hole quadrupole moment measurements of black hole-pulsars. We find that bounds on the parity-violating sector of quadratic gravity can be stronger than current bounds by six orders of magnitude. These results suggest that a new discovery of black hole-pulsars in the future will provide powerful ways to probe gravity further.