Dynamics of compact stars in extreme gravitational fields

2015年，来自合并黑洞的引力波的发现标志着引力波天文学的曙光，这是一项巨大的科学发展，并获得了2017年诺贝尔物理学奖。引力波是时空结构中的涟漪，由大质量物体的加速运动产生。它们的产生需要在宇宙中找到密度最高的物体，如中子星和黑洞，这些物体必须以极快的速度运动，当它们形成紧密的双星系统时就是这样。它们的测量需要大型专用设施，如LIGO和处女座天文台。探测到多个引力波来源，包括黑洞和中子星，是LIGO/处女座合作的一大胜利，这项工作仍在进行中。引力波天文学打开了一扇了解宇宙的新窗口，以便更好地观察宇宙最黑暗的部分。 我研究的长期目标是利用引力波天文学来极大地提高我们对中子星和黑洞的理解。为了实现这一目标，我和我的学生们阐明了当两个这样的物体形成紧密的二进制时，发挥作用的物理过程。例如，一颗中子星在伴随的中子星上引起潮汐，就像月球在地球上引起潮汐一样，潮汐变形影响它们的轨道运动和引力波的发射。波浪上的潮汐印记是可以测量的，这将揭示中子星物理的秘密细节。这是非常令人兴奋的，因为人们对中子星知之甚少，涉及的物质密度远远超过地球上可以找到的物质密度。作为另一个例子，两个黑洞之间的潮汐相互作用改变了每个物体的质量和自转，这可以从发射的引力波中揭示出来。这也是非常令人兴奋的，因为波中的潮汐效应将揭示黑洞一些最难以捉摸的属性，例如它的活动视界的形状。 这项研究提案的目的是进一步研究中子星和黑洞，以便更好地预测此类天体发出的引力波。为了实现这一点，我和我的学生将使用理论物理技术，操纵支配黑洞、中子星和引力波的物理定律，以提取准确的预测，与更广泛的科学界分享。

The 2015 discovery of gravitational waves from merging black holes marked the dawn of gravitational wave astronomy, a tremendous scientific development that was rewarded with the 2017 Nobel Prize in physics. Gravitational waves are ripples in the fabric of spacetime, produced by the accelerated motion of massive bodies. Their production requires the most dense objects to be found in the universe, such as neutron stars and black holes, and these objects must move extremely rapidly, which is the case when they form a tight binary system. Their measurement requires large dedicated facilities such as the LIGO and Virgo observatories. The detection of several sources of gravitational waves, involving both black holes and neutron stars, is a great triumph of the LIGO/Virgo collaboration, and the effort is ongoing. Gravitational-wave astronomy opens up a new window onto the universe, to better observe its darkest reaches. The long-term goal of my research is to exploit gravitational-wave astronomy to dramatically improve our understanding of neutron stars and black holes. To reach this goal, my students and I elucidate the physical processes at play when two such objects form a tight binary. For example, a neutron star raises a tide on a companion neutron star, much as the moon raises a tide on Earth, and the tidal deformation affects their orbital motion and the emission of gravitational waves. The tidal imprint on the waves can be measured, and this will reveal intimate details of the physics of neutron stars. This is very exciting, because neutron stars are poorly understood, involving densities of matter that are far beyond what can be found on Earth. As another example, the tidal interaction between two black holes changes the mass and spin of each object, and this can be revealed in the emitted gravitational waves. This also is very exciting, because the tidal effects featured in the waves will reveal some of the black hole's most elusive properties, such as the shape of its event horizon. The goal of this research proposal is to further the study of neutron stars and black holes, so as to better predict the gravitational waves emitted by such objects. To carry this out, my students and I will use the techniques of theoretical physics, manipulating the laws of physics governing black holes, neutron stars, and gravitational waves, so as to extract precise predictions to be shared with the wider scientific community.