Optical analogy of gravitational collapse and quantum tunneling of the event horizon

We present an optical method to realize the analogy of gravitational collapse by using the gradient of the refractive index system and the spacetime embedding diagram. We observe an analogy of Hawking radiation after the horizon is formed, for which the corresponding effective temperature is obtained via the transmission spectrum. We find that the effective temperature is proportional to the surface gravity, which is similar to the case in real black holes. (paper)