There are to many variables missing to even debate if physics have been broken or not.
What speed is the elevator traveling? How much force is being applied to the character by gravity?
If the elevator is moving downwards at the characters terminal velocity, when the character jumps, he'll break free from the surface of the elevator. The character wouldn't make contact again until the elevator began to decelerate. The rate of deceleration would determine the amount of force applied to the character when they make contact with the elevator floor.