Gravitational red shift, also known as gravitational blueshift, is the phenomenon where light from an object appears to have longer or shorter wavelengths due to the effect of gravity. This is caused by the gravitational pull of massive objects like stars or black holes, which can warp the fabric of space-time and alter the wavelength of light.
Gravitational red shift occurs due to the effect of gravity on light, while Doppler red shift is caused by the relative motion between the source of light and the observer. Gravitational red shift can occur even in the absence of motion, whereas Doppler red shift requires a change in the distance between the source and observer.
The existence of gravitational red shift was first predicted by Einstein's theory of general relativity. It has since been observed in astronomical objects such as stars, galaxies, and even the cosmic microwave background radiation. The phenomenon is also supported by numerous experiments and observations in the field of physics.
According to Einstein's theory of general relativity, time moves slower in the presence of strong gravitational fields. This means that clocks in a strong gravitational field will appear to tick slower than those in a weaker field. Gravitational red shift is one of the effects that contribute to this time dilation phenomenon.
No, gravitational red shift cannot be reversed. This is because it is a natural consequence of the bending of space-time by massive objects. In order to reverse the effect, one would need to counteract the gravitational pull of these objects, which is not possible with current technology.