Timestream Physics

The timestream is a current of probability, flowing through the fourth and fifth dimensions.  The physical (3D) universe is an aspect of the timestream, existing simultaneously in all points along the stream.  Typically this current exists in one path of continuity - a primary timescape, as it were.

The timestream itself is not laid in stone.  As the universal life-essence flows along the timescape, different events will occur, typically as a result of the free will of all living things.  For each one of these events - no matter how large or small - a temporal divergence will occur.  One or more threads of time-reality will branch off from the primary timescape, in which the probabilities are different.  In short, a parallel universe is created.  Typically, the differences between these spawned realities and the primary timescape are very small;  eventually the probability makeups will sync up, and the parallel reality will converge with the primary timescape.  The time that it takes for convergence to happen is directly related to the relative size of the divergence to the size of the universe. That is to say that large divergences tend to take aeons to completly converge where as small divergences can converge in a matter of minutes after the original divergence.  The entire timestream exists in such a state of flux - side-realities phasing in and out of the current, diverging and converging.  So it has gone, throughout infinity.

However, there is one possibility that has dire consequences for the timestream - temporal travel.  A mysterious element known as Zexonyte exists throughout the universe in large quantities.  This element, a radioactive material, can exert strong gravi-magnetic forces on the fabric of the fourth and fifth dimensions.  Through an inverse tripolar field, a fragment of Zexonyte can distort time.

Focused Zexonyte radiation can cause distortions in the fourth and fifth dimensions that cause movement through the fourth dimension, i.e. time travel. In the case of time travel, it is possible in certain circumstances for the primary timeline to diverge into two, equal primary timelines, both with the same statistical probability of existance. In this case, a phenomenon occurs that allows time travelers from both primary timelines to travel into the past before the point where the timelines split. This often causes the point of divergence into the two primary timelines to be destroyed thereby destroying one of the primary timelines. In cases where this does not occur, the two timelines converge over time as random chances lead the two timelines' events together. Often the divergences involved with time travel are rather large and thus take a long time to completly converge. For example, for the two primary timelines created by the destruction of Giygas to completly converge will most likely take until the end of Earth's solar system to completly converge.  However, over time the differences will become so small that they will be nearly impossible to determine.