Constraints on the variation of the gravitational constant G have been obtained by many observers using different methods, the most reliable and stringent being those based on the orbital timing of bodies in the solar system and binary pulsars. We show that the constraints determined from orbital timing are on rather than on when the speed of light c is also considered to be varying. Increasingly tighter constraint on from these observations are possibly due to . This relationship between G and c was determined in a previous work by fitting the supernovae 1a data using the relativistically covariant cosmological model with varying and cosmological constant Λ.

许多观测者使用不同的方法获得了对引力常数G变化的约束，其中最可靠和最严格的是基于太阳系中天体和双星脉冲星的轨道时间的约束。我们表明，当光速c也被认为是变化的时，由轨道时间确定的约束是打开的，而不是打开的。对这些观察结果越来越严格的约束可能是由于。G和c之间的这种关系是在之前的工作中通过使用具有变化和宇宙学常数 Λ的相对论协变宇宙学模型拟合超新星 1a 数据来确定的。