String theory is an attempt to create a "Theory of Everything" - a theory that unifies the electromagnetic, strong and weak nuclear and gravity forces. Note: the electromagnetic and weak nuclear forces have been unified into an "electroweak force", much like the unification of the Guardian and Observer newspapers, two entirely different things stuck together with cosmic glue.

The basis of the theory is that all matter is composed of superstrings. These are much the same as supernoodles, only they are incredibly small. So small in fact, that a flea could eat a million of them, and still hanker after a doner kebab with all the toppings. The strings themselves are, in fact, the smallest possible particles, with a length of 10^-33 cm, and no width or height. This is a lot shorter than the length most people would give when asked the question “How long is a piece of string?”. In fact most people use this question as a way of not giving you information you require, on the basis that no-one could possible answer the question you have just asked. When you give them a confident and precise response to their question, they will be so shocked they will probably die of apoplexy, or hit you very hard, depending on whether their brains or their arms react faster.

Strings can be open or closed. Closed strings have the shape of a circle or oval, and open strings have ends. So A string occupies one single point in space-time at any one time. Space-time is excellent, because rather than space being an empty nothingness, it's actually an incredibly curvy, dilational empty nothingness, where you not only have to ask yourself, "where the f**k am I?", but also "When the f**k am I?" Its path through time can be shown in a space vs time graph, and is called a worldsheet. The superstring theory can describe the four forces (electroweak, strong nuclear, and gravitational) if the tension in the string is 10³⁹ tons. The predictions of this theory are identical to general relativity in most cases. However, at a distance of 10^-33cm, the two theories differ.

One problem with string theory is that it only works in ten or twenty-six dimensions. This is because if there are any other number of dimensions, mathematical anomalies appear. The question then has to be asked, where are the other six dimensions? In normal life there are only four, unless you are particularly drunk, in which case there are only two. However, it is possible that the six dimensions that we cannot see curled up into tiny balls just 10^-30 inches long. It is theorised that they curled up just after the Big Bang. It is possible that if some variables in the Big Bang were different to what they turned out to be, some or all of these extra dimensions would have expanded. What would such a universe look like? An extremely large bowl of spaghetti? Milton Keynes? Obviously, our 4-dimensional perceptions cannot imagine what it would be like, but the possibility of it happening remains. As such distances are too small for us to see, they could go unnoticed but still be there.

String theory states that the electroweak and strong forces have the same strength at an energy of 10¹⁶GeV, and that gravity as well will have the same strength at 10¹⁹GeV. If all the forces have the same strength, an equation can be written to describe them. (At least, that's the theory)

Originally there were five separate string theories, each one of them working in different situations (rather than describing different pieces of string). These, in 1994, were unified into a single "M-theory". M-theory may only holds true in eleven dimensions, which is different from the original ten, but hey, of you haven't missed the other six dimensions, one more is hardly going to be a problem.

The theory has not been fully fleshed out. There are many advancements still to make. It may be that an "F-Theory" (F for father) will emerge, a string theory that involves strings being present in either ten, eleven or twelve dimensions. However, we are still far from the ultimate Theory of Everything or "TOE".