Time is the presence of motion and forces. Time is due to expansion of space. Time is slow where expansion of space is slow like around large masses. As total motion and forces within a mass is a constant therefore when linear motion is increased then internal motion as well forces within that object slow which is then percieved as slowing of time. If we think of two objects in orbit around each other and imagine time slowing down then we should motion slow down as well as forces get weaker. Forces are part of time. Forces determine the arrow of time. Without forces time will be perfectly symetrical and lack any direction.