If the quantity of matter within the currently expanding universe is beneath a certain threshold, the universe will continue expanding forever. Just as we cannot place ourselves within a central location of position within the universe, we cannot place ourselves within a central location of time. This means that an expanding universe that has no end also has no beginning. As such, the universe has no creator. This does not mean that neither a God, nor a multitude of Gods, exists. It means that the universe has always existed along with the God, or multitude of Gods.
