标题： 通过引力波对违反洛伦兹不变性的引力理论的约束 显示英文标题

标题： Projected Constraints on Lorentz-Violating Gravity with Gravitational Waves

摘要： 引力波是探测广义相对论在强动力和非线性区域基础的优秀工具。 其中一个基础是洛伦兹对称性，它可能由于存在一个优先的时间方向而在引力领域被破坏，因此在每个时空点上有一个优先参考系。 这会导致双星系统的轨道衰减率发生变化，以及它们相关的引力波的产生和啁啾发生变化。 我们在此研究，在非自旋中子星双星的晚期准圆 inspiral 中发射的引力波是否可以对两个引力洛伦兹破坏的代理进行有竞争力的约束：爱因斯坦-\AE{}理论和khronometric 引力。 我们在小耦合（或解耦）极限和后牛顿近似中对这些波进行建模，通过微扰求解从广义相对论的小变形和小速度/弱引力近似中得到的场方程。 我们假设已用第二代和第三代地面探测器以及提议的空间任务 DECIGO 检测到与广义相对论一致的引力波，并且在有和没有同时电磁对应物的情况下。 如果没有对应物，仅使用未来的第三代或空间仪器，才能对引力洛伦兹破坏施加有竞争力的约束。 另一方面，一个对应物就足以施加比当前双脉冲星限制严格十倍的约束，即使使用第二代探测器也是如此。 这是因为洛伦兹破坏会使引力波的群速度不同于光速，而这种差异可以通过同时观测非常精确地约束。 显示英文摘要

摘要： Gravitational waves are excellent tools to probe the foundations of General Relativity in the strongly dynamical and non-linear regime. One such foundation is Lorentz symmetry, which can be broken in the gravitational sector by the existence of a preferred time direction, and thus, a preferred frame at each spacetime point. This leads to a modification in the orbital decay rate of binary systems, and also in the generation and chirping of their associated gravitational waves. We here study whether waves emitted in the late, quasi-circular inspiral of non-spinning, neutron star binaries can place competitive constraints on two proxies of gravitational Lorentz-violation: Einstein-\AE{}ther theory and khronometric gravity. We model the waves in the small-coupling (or decoupling) limit and in the post-Newtonian approximation, by perturbatively solving the field equations in small deformations from General Relativity and in the small-velocity/weak-gravity approximation. We assume a gravitational wave consistent with General Relativity has been detected with second- and third-generation, ground-based detectors, and with the proposed space-based mission, DECIGO, with and without coincident electromagnetic counterparts. Without a counterpart, a detection consistent with General Relativity of neutron star binaries can only place competitive constraints on gravitational Lorentz violation when using future, third-generation or space-based instruments. On the other hand, a single counterpart is enough to place constraints that are 10 orders of magnitude more stringent than current binary pulsar bounds, even when using second-generation detectors. This is because Lorentz violation forces the group velocity of gravitational waves to be different from that of light, and this difference can be very accurately constrained with coincident observations.