The light should accelerate towards the earth, the same way as massive objects are attracted towards the earth[General relativity]. We may not find path of the light to be curved because of the enormous velocity of light, the curvature of light is too subtle for our senses. Consider a thought experiment: There are two vertical mirrors on the earth. If a horizontal light pulse is shone on one mirror, the light pulse will repeatedly bounce between the two mirrors. Since the gravity is acting on the light pulse, the light pulse will began to move downwards with the passage of time. The vertical position of the light pulse can be given by: s = ut +0.5g(t^2) Is there any flaw in my thought experiment? If not, is this done experimentally by anyone yet?