by Stavros Mouslopoulos (theoretical particle physicist) and Anastasia Joyce.

The cutting edge of particle physics deals with the possibility of 11 dimensions and parallel universes.

Most of us can understand four dimensions. (The three Spatial Dimensions of left to right, up and down and backwards and forwards; and the Time Dimension or fourth dimension.)

Physics is now looking at an M- Theory (sometimes called the Membrane Theory). This provides some theoretical answers to problems posed by String Theory which tried to explain everything including the Big Bang. Put very simply it involves space being curled up within a whole lot of other dimensions.

This M-Theory provides answers to some of the long standing problems physicists have been grappling with in a search for a perfect Grand Unifying Theory (GUT). Not only that but the M-Theory favors the possibility of parallel universes.

So if the M-Theory is correct and there are parallel universes would those universes be waste free? The simple answer is "no" because of the Second Law of Thermodynamics.(See: http://www.wotwaste.com/waste-articles/universal-waste/the-universal-law-of-waste-part-1-or-the-chicken-corn-and-egg-in-a-lonely-cosmic-journey )

However this question does raise the hot philosophical debate of determinism versus free-will.

A strict determinist would propose that within these parallel universes there would be humans, identical to us making identical mistakes and causing identical problems. That's because every event is determined by an unbroken chain of prior events over which there is no control: Humanity is hopeless in the face of physical laws.

Someone who believed in free-will however would propose it was possible these parallel universes contained living beings (perhaps humans) who were able to predict, measure and modify the results of actions. Therefore while a parallel universe would still produce waste maybe its world, or worlds, might not be polluted.