Relativistic Astrophysics of Neutron Stars

中子星和黑洞是宇宙中最致密的天体。它们强大的引力场使我们能够探索在地面实验中无法到达的物理体系，并检验引力物理理论。虽然黑洞是相当简单的物体，但中子星却相当困难。这是因为它们是物质密度最大的结构，对引力坍缩是稳定的。中子星中心核心的密度可以比核物质的密度大很多倍。由于地球上的实验无法重现如此高的密度，中子星的内部结构还没有得到很好的理解。特别是，如果有可能测量中子星的大小，它将有助于我们了解超核密度物质的性质。这项研究计划的主要重点是中子星动力学的理论研究，重点是它们产生的电磁辐射。对含有中子星的系统（如脉冲星、x射线双星、磁星和短伽马射线暴）发出的光的观测，提供了大量的数据来比较理论预测。拟议的研究将涉及光在快速旋转的中子星附近传播的计算研究，以便对相对论效应（如框架拖拽和引力透镜）做出理论预测，这些效应可能被当前和未来提议的x射线望远镜探测到。这项工作将在测量许多中子星的大小和其他特性方面发挥重要作用，使我们能够约束描述中子星内部致密核物质的可能理论。

Neutron stars and black holes are the most compact astrophysical objects in the universe. Their strong gravitational fields allow us to explore a regime of physics inaccessible in terrestrial experiments and to test theories of gravitational physics. Although black holes are reasonably simple objects to describe, neutron stars are considerably more difficult. This is because they are the densest configurations of matter possible which are stable to gravitational collapse. The density in the central core of a neutron star can be many times more dense than nuclear matter. Since experiments on Earth can't reproduce such high densities, the internal structure of a neutron star is not well understood. In particular, if it were possible to measure the size of a neutron star, it would help us understand the properties of supranuclear density matter. The main focus of this research proposal is a theoretical study of neutron star dynamics with an emphasis on the electromagnetic radiation they produce. Observations of light originating from systems containing neutron stars, such as pulsars, x-ray binaries, magnetars, and short gamma-ray bursters, provide a great wealth of data with which to compare theoretical predictions. The proposed research will involve computational studies of the propagation of light near rapidly rotating neutron stars in order to make theoretical predictions about relativistic effects (such as frame-dragging and gravitational lensing) which may be detectable by present-day and future proposed X-ray telescopes. This work will play an important role in measuring the size and other properties of many neutron stars allowing us to constrain the possible theories of dense nuclear matter which describe the interior of a neutron star.