论文标题
GW170817的宇宙学和修饰重力的关节测试
Joint tests of cosmology and modified gravity in light of GW170817
论文作者
论文摘要
在这封信中，我们首次通过结合GW170817的GW和电磁观测来结合宇宙学和修饰的重力理论。我们为哈勃常数$ h_0 $提供联合后验分布，以及典型的修饰重力的物理效应：重力波（GW）摩擦，由参数$α_m$编码，以及几种GW分散关系。在此分析的结果中，我们可以使用同一事件的测量值提高重力质量的限制，但要固定$ H_0 $。我们获得$ m^2_g = 2.08 _ { - 4.25}^{+13.90} \ cdot 10^{ - 44} \ rm {ev^2/c^4} $在99.7 \％置信度（Cl），当时在hubble常量和gw friction term $ a $ $ alliction $ alliction $ agm上。我们发现对$α_M$的限制不佳，但证明，对于所有考虑的GW分散关系，包括大量重力，GW必须在伽马射线爆发（GRB）之前排放$ \ sim $ 1.74。此外，在GW合并峰值频率下，我们表明GW组速度和$ c $之间的分数差异为$ \ sillesim 10^{ - 17} $。
In this Letter we constrain for the first time both cosmology and modified gravity theories conjointly, by combining the GW and electromagnetic observations of GW170817. We provide joint posterior distributions for the Hubble constant $H_0$, and two physical effects typical of modified gravity: the gravitational wave (GW) friction, encoded by the parameter $α_M$, and several GW dispersion relations. Among the results of this analysis, we can improve by 15\% the bound of the graviton mass with respect to measurement using the same event, but fixing $H_0$. We obtain a value of $m^2_g=2.08_{-4.25}^{+13.90} \cdot 10^{-44} \rm{eV^2/c^4}$ at 99.7\% confidence level (CL), when marginalising over the Hubble constant and GW friction term $α_M$. We find poor constraints on $α_M$, but demonstrate that for all the GW dispersions relations considered, including massive gravity, the GW must be emitted $\sim$ 1.74s before the Gamma-ray burst (GRB). Furthermore, at the GW merger peak frequency, we show that the fractional difference between the GW group velocity and $c$ is $\lesssim 10^{-17}$.
