[Andre]

While it is true that the first machines designed to cure and provide therapy for cancers used high-energy protons and other forms of radiation, such as X-ray and gamma rays, it has been proven that they can cause tissue damage along their path.

A proton has a rest mass (before acceleration) 1,836 times greater than that of an electron, so it can be made into a heftier projectile. Protons are also easier to accelerate to high energies than are electrons, and accelerators that collide opposing beams of protons (or opposing beams of protons and antiprotons) have been called ''discovery machines'' because of some dramatic successes they have achieved in recent years.

However, protons, which contain three quarks each, have been likened to bean bags. When two protons collide head on, the collisions are actually between their component quarks, and the complex showers of secondary particles that emerge are very difficult to decipher.

This is a cause for great concern as measurements involving these collision can't be made in precision, therefore not allowing scientists to discern some of the fine details of physical relationships that are hidden in the complex showers emerging the collision.