13 Dec 2011

‘Signs’ of Higgs boson particle found

Scientists at the Cern European physics research centre say they have found signs of Higgs boson, the so-called “God particle” and the missing link of particle physics.

Scientists have long been searching for the Higgs boson particle because its existence proves the theory about the existence of the Higgs field, which they say gives mass to all particles in the universe.

The Higgs field works by restricting the speed of particles it interacts with, which would otherwise zip around the universe at the speed of light.

The field acts in the opposite way to, for example, a person who “becomes” lighter when swimming in water.

Scientists at the Cern physics research centre near Geneva said, however, they had found no conclusive proof of the existence of the particle.

“If the Higgs observation is confirmed…this really will be one of the discoveries of the century,” said Themis Bowcock, a professor of particle physics at Liverpool University.

“Physicists will have uncovered a keystone in the makeup of the Universe…whose influence we see and feel every day of our lives.”

The leaders of two experiments, Altas and CMS, revealed their findings at Cern, where they have tried to find traces of the elusive boson by smashing particles together in the Large Hadron Collider at high speed.

“Both experiments have the signals pointing in essentially the same direction,” said Oliver Buchmueller, senior physicist on CMS. “It seems that both Atlas and us have found the signals are at the same mass level. That is obviously very important.”

Prof Stefan Soldner-Rembold, from the University of Manchester said: “Within one year we will probably know whether the Higgs particle exists, but it is likely not going to be a Christmas present.”

Higgs boson explained - graphic

Higgs boson – a Hollywood star

The theory, expounded by British physicist Peter Higgs in the 1960s, talks about the field as a kind of lattice that filled the entire universe, 100th of a billionth of a second after the Big Bang.

Elementary particles, with no mass, had previously been whizzing around at the speed of light. But once the massless particles passed through the field, Higgs boson particles became highly attracted to them, creating friction and slowing the particles’ movement.

Some types of particle travel through the field virtually unimpeded, others dragged to slower velocities by varying amounts.

As the particle slowed, their energy was condensed into a super-concentrated form of energy: mass. Therefore, the slower the particle is made to go, the greater its mass becomes.

Cern has often referred to the analogy of a bustling Hollywood party.

When a celebrity arrives, the crowd is evenly distributed around a room. When the famous actress arrives, the people closest to the door swarm around her. As she walks through the room, she constantly attracts the people closest to her.

When she gets far enough away, parts of the crowd return to their other conversations. So by restricting her movements across the room, the crowd are giving her mass.

Without the Higgs field, particles would never have merged together to form atoms and molecules and, in turn, stars and planets.

The Higgs boson itself, like other bosons which have actually been observed, are the smallest fundamental units of matter in the universe. Smaller than atoms, smaller than their components, and smaller than the compenents of their components.