Light, which travels at the speed of light (c), is not subject to time dilation as experienced by massive objects. According to the theory of special relativity, objects with mass experience time dilation as their velocity approaches the speed of light relative to an observer at rest. However, light itself does not experience time dilation because it always moves at the maximum speed allowed in our universe.
The concept of time dilation arises from the fact that the passage of time is relative and depends on the relative motion between two observers. However, from the perspective of a photon of light, no time elapses. This means that, from the photon's frame of reference, it is emitted and then immediately absorbed, without any time passing in between.
When we talk about reflection, we're referring to the interaction of light with a surface. When light hits a surface and reflects, the process involves the absorption and re-emission of photons by the atoms or molecules in the material. This interaction occurs at the microscopic level and is governed by the laws of electromagnetism.
Although light itself does not experience time dilation, the interaction of light with matter can be influenced by gravitational fields. Gravitational fields can cause a bending of light, known as gravitational lensing, as predicted by general relativity. This bending occurs because the gravitational field curves the fabric of space-time, altering the path of light.
So, while light is not subject to time dilation, it can be influenced by gravitational fields and can exhibit behaviors such as bending and being affected by the geometry of space-time. These phenomena have been observed and confirmed through experiments and astronomical observations.