Universe’s elusive quark particle has been proven to exist

Two physicists have made a breakthrough in the long-running search for confirmation of the tetraquark

For half a century, physicists have been fascinated by quarks – those tiny elementary particles which combine in groups of three to form hadrons such as protons and neutrons.

They've also been obsessed with trying to prove whether or not four quarks can stably combine to create a tetraquark. But now it seems there is confirmation that they can.

Physicists Marek Karliner of Tel Aviv University and Jonathan Rosner of the University of Chicago have been calculating the outcome of different quark combinations. They knew that the heavier quarks – those termed ‘charm’, ‘top’, ‘strange’ and ‘bottom’ (as opposed to the lighter ones, ‘up’ and ‘down’) – are better able to bond into hadrons. They were also aware that doing so in groups of three leads to stability, whereas four causes potential instability, mainly because of issues with the strong forces which help hold them together.

However, they have found that one combination does appear to work. By putting a doubly charmed baryon (a hadron made of two charm quarks and a lighter quark) together with a double-bottom baryon they found that – theoretically at least

– a stable quark emerges. It is also likely that this true tetraquark can be generated using CERN's Large Hadron Collider (LHC). “The upshot of all this is that we now have a robust prediction for the mass of this object which had been the holy grail of this branch of theoretical physics for quite some time," Karliner concludes.

RNA is made of a family of molecules called nucleobases that could not have formed on a lifeless early Earth The hope is that the Large Hadron Collider will eventually find a tetraquark