Mechanism of time, bitch.
Time is defined however we want it to be. That's like saying what's the mechaninsm for length.
Length is not an action or a force, it is a measurement of space.
Length does not inherently exist, it is a human invention.
Time observably exists, and can be manipulated by gravity.
Time is the method you use for accurately triangulating position using millions of cell phones.
EXPLAIN THE MECHANISM, OR YOU CANNOT BELIEVE IN TIME!