If Newton was wrong about gravitation. Everything that we learned in school about gravitation is wrong. During Newton's time, gravitation is the force that pulled an apple to the ground. Gravitation is interaction. And also apple pulls Earth to it. So in that interaction, both sides of gravitation are moving. But Earth's movement is so small that we cannot measure it. In normal life, that thing is meaningless, but if we would drop apples to a certain point on Earth, let's say, about a billion years that thing can change Earth's t trajectory. There must be errors in Newton's calculations. The gravitational model was not complete when Newton lived. In his lifetime there was no knowledge about the thing called gravitational waves. Gravitational waves travel in the universe at the speed of light. We know that origin of those waves that are like all other radiation is in objects. The requirement of those gravitational waves is that object has mass. Why can gravitationa