I asked a question concerning this subject once but the discussion dissolved into petty quibbling and I saw no links or evidence to back up or help me understand any of the statements made. What is the relationship between time dilation and the effect of gravity? This was my original post. Time dilation relationship between gravity and velocity. Spaceships A and B synchronise their atomic clocks and then perform an activity :Spaceship A accelerates to 0.9999 times the speed of light in relation to spaceship B. Time in spaceship A will be observed by spaceship B to be running slower by the factor (Va^2/C^2)^-0.5=Tb/Ta Where Tb/Ta is the ratio of Tb compared to Ta and Va is the velocity at which spaceship A has accelerated from B. In this case Tb/Ta = 1.00010001, so time at spaceship B is going 1.00010001 times faster than time in spaceship A. ;Spaceship A flies to a black hole and is affected by an acceleration of 100000ms^-2 due to the force of gravity and spaceship B remains in negligible gravity. Has anyone found out what Tb/Ta is in relation to gravity and can a simple simultaneous equation find out a relationship between Gravity and Velocity?