Out of the four multiverse hypotheses, the level III multiverse has generated the most controversy despite being, on a cursory level, the most elementary. Simply phrased, the existence of a level III multiverse is based on the theory that all states of the universe exist in some abstract space. Whereas in the other levels, parallel universes are theorized to be located in regions of space unobservable to us, the level III multiverse can be thought of as states all around us, yet in a different dimension beyond our comprehension. While it may appear that there are an infinite amount of states, the amount of mass-energy in the Hubble volume—or the observable universe—leads to a different belief. Since there are a finite amount of particles that exist, there must be a finite amount of ways these particles can be placed. These states are all static and what we—as humans—observe as time and change can instead be thought of as a smooth series of shifts from one state of the universe to another.
The idea of testing for the existence of a level III multiverse has been pondered over by many. Perhaps the most morbid speculated experiment is quantum suicide. The premise behind the experiment is the existence of a life-terminating device, such as a gun, held to a subject. Every ten seconds, the gun is either fired and the subject dies, or is not fired, providing another ten seconds before the next shot. If all possible static states of the universe indeed exist, then in some state, the gun will not fire for an infinite amount of time. Therefore, the longer the subject exists, the more credibility the theory gains.
While the scientific basis behind this theory is far from fully established, the possibility of a level III multiverse has many interesting philosophical implications. Assuming the existence of a level III multiverse to be true, the idea of one can be said to hold similar ideals to those people that believe in fate. With every possibility already existing, proponents of this belief would claim that any action we make is predetermined. In a similar vein, the opposite viewpoint can also be supported by the existence of a level III multiverse. As people living only in the present, there are an uncountable amount of other copies of “us,” each having made different decisions and having experienced different lives. Perhaps this tells us that rather than subjecting our experiences to a predetermined life, it can be said all versions of “us” are experiencing every possible decision there is to make: both good and bad.
- Alex Du