The three-lined glowing part in the time machine resembles the Flux Capacitor, the main piece from the DeLorean DMC-12 Time Machine to travel in time from the Back to the Future movies.
Cyborg mentions that changing one little thing in the past will completely change the future similar to the events in this movie where chaning the past will always have unintended consequences.
Beast Boy and Robin cut the pizza in half this time that triggers time waves that change the present bit by bit similar to how in A Sound of Thunder when accidental killing of a butterfly literally triggers time waves that change the present bit by bit.