The effect of gravitational waves on light depends on the specific conditions and geometry involved. Gravitational waves are ripples in spacetime caused by the acceleration of massive objects, such as black holes or merging neutron stars. When gravitational waves pass through an area, they can cause stretching and compressing of spacetime along different directions, resulting in a phenomenon known as gravitational wave strain.
The interaction between gravitational waves and light is described by the theory of general relativity. According to this theory, the path of light is influenced by the curvature of spacetime caused by the presence of mass and energy. When gravitational waves pass through an area, they can cause fluctuations in the curvature of spacetime, which can potentially affect the path of light.
If a red light wave (or any other color of light) encounters a region of spacetime that is being stretched or compressed by a passing gravitational wave, it can experience a change in its wavelength. This phenomenon is known as gravitational redshift or blueshift, depending on the direction of the strain.
In the case of a passing gravitational wave, the effect on a red light wave would depend on the orientation and strength of the wave, as well as the distance between the wave and the light. If the gravitational wave is sufficiently strong and passes close by, it could cause a detectable change in the wavelength of the red light. However, for most everyday scenarios involving gravitational waves, the effects on light would be extremely small and difficult to detect without highly sensitive instruments.
It's worth noting that the most significant effects of gravitational waves are typically observed in astrophysical events involving massive objects, such as black hole mergers or neutron star collisions. In such cases, the gravitational wave strain can be extremely powerful, leading to observable effects on light, such as gravitational lensing or changes in the electromagnetic radiation emitted by the objects involved.