Near a supermassive black hole, time dilation can occur due to the strong gravitational field generated by the black hole. According to Einstein's theory of general relativity, gravity is not just a force but rather a curvature of spacetime caused by massive objects.
When an observer approaches a supermassive black hole or enters its vicinity, the gravitational field becomes increasingly intense. As a result, time dilation effects become more significant. The closer an observer is to the black hole's event horizon (the boundary beyond which nothing can escape, including light), the stronger the gravitational field and the more pronounced the time dilation.
The gravitational time dilation near a black hole can be described in two scenarios:
Time dilation due to gravitational potential: As an observer approaches a supermassive black hole, they experience a stronger gravitational potential. This leads to time dilation, where time appears to slow down for the observer relative to an observer located further away from the black hole. This effect is similar to the time dilation experienced in a weaker gravitational field, such as near Earth's surface but significantly amplified near a supermassive black hole.
Time dilation due to gravitational time dilation: In addition to the gravitational potential effect, another form of time dilation called gravitational time dilation occurs near a black hole. This effect arises due to the variation in the gravitational field's strength at different distances from the black hole. Clocks closer to the black hole tick more slowly compared to clocks further away. This means that time appears to pass more slowly for an observer closer to the black hole relative to an observer located farther away.
The combination of these effects near a supermassive black hole can lead to significant time dilation, where time appears to slow down or dilate relative to observers further from the black hole. This phenomenon has been observed indirectly through various astronomical observations, such as the motion of matter falling into black holes and the behavior of light near their event horizons.