"The trail leading to the Unified Field Theory is littered with the wreckage of failed expeditions and dreams..." (Dr Michio Kaku. Theoretical physicist, futurist and author.)

A common joke within the theoretical physics community is that 90 percent of theories published will be, at some time, proved to be wrong.

Albert Einstein unsuccessfully spent years looking for the tail of the lion. The theory that would finally lead to the roar of a perfect Grand Unification Theory (GUT).

Einstein's GUT attempt is one of many by physicists. There is Trinification, Flipped SU(5), Flipped SO(10), the left-right model, the Georgi-Glashow model and so on and so forth. All have attempted to unite the electromagnetic, weak nuclear and strong nuclear forces into one field of space and time.

In so doing they have wrought havoc on accepted and respected beliefs such as the stability of protons. That one has been tossed out by some in favour of the partial instability of protons. (Thus more wreckage and litter on the way to GUT.)

Another problem with GUT is the absence of the smoking gun, the Higgs particle. The existence of this particle is still a theory. It is sometimes called the "God particle". If it exists it would explain how mass is given to all other particles in the universe. The thing is while physicists can measure mass, they can't explain or predict how mass should appear.

Finding Higgs would confirm something called the electroweak force (the combination of weak and electromagnetic interactions into one theory). This theory says weak forces are closely related to electromagnetic forces and have essentially equal strengths. They just appear to have different strengths because of the effect distance and mass have on the interaction of the forces. And that's the problem, without Higgs, we can't predict how mass would occur anywhere, let alone in this theory. Oh dear.