Isaacs (named after Isaac Newton are a unit of space; they are formed of a similar structure to atoms and fill the space between the atomic nuclei. They are made up of a Tree (which does not grow like any old tree but in fact shrinks) particle in the centre being orbited by a number of Apple particles (which it seems can be eaten however there small size means that it is impossible to tell weather they really taste like cabbage or beef). The Tree particle emits Apples particles like radiation which causes the Apple particles have a spiral orbit slowly moving away from the tree particle in the centre of the Isaac. This result in Isaac’s expanding constantly and so increasing the amount of empty space in the universe, ultimately resulting in the universe expanding.