Britain's Peter Higgs and Francois Englert of Belgium won the Nobel Prize for physics on Tuesday for predicting the existence of the Higgs boson particle, which explains how elementary matter attained the mass to form stars and planets.
The insight has been hailed as one of the most important in the understanding of the cosmos. Without the Higgs mechanism, all particles would travel at the speed of light and atoms would not exist.
Half a century after the scientists' original prediction, the new building block of nature was finally detected in 2012 at the European Organization for Nuclear Research (CERN) center's giant underground particle-smasher near Geneva.
"I am overwhelmed to receive this award," said Higgs, who is known to shun the limelight and did not appear in public on Tuesday despite winning the world's top science prize.
"I hope this recognition of fundamental science will help raise awareness of the value of blue-sky research," he said in a statement via the University of Edinburgh, where he works.
The two scientists had been favorites to share the $1.25 million prize after their theoretical work was vindicated by the CERN experiments.
To find the elusive particle, scientists at the Large Hadron Collider had to pour over data from the wreckage of trillions of sub-atomic proton collisions.
Johns Hopkins University and University of Maryland scientists were among those who joined in the hunt for the Higgs boson.
"The challenge was to actually see the Higgs bosons once they are created," said Andrei Gritsan, experimental physicist and associate professor in Hopkins' Henry A. Rowland Department of Physics and Astronomy, who helped plan and implement experiments using the CERN accelerator, the word's largest.
"One aspect is to make the scientific instrument … as precise as possible. With my team at Hopkins and leading a group of several experts, I developed the methods to precisely focus the key system of the detector, the silicon tracking system, to see the Higgs boson traces."
His team also developed methods to collect the maximum data so scientists could confidently identify a Higgs particle.
The five Hopkins and 22 Maryland scientists were among 1,300 U.S. researchers from 89 universities and seven U.S. Department of Energy labs who worked on two teams, according to University of Maryland officials. The overall international collaboration made possible the fundamental discoveries.
The Higgs boson is the last piece of the Standard Model of physics, which describes the fundamental make-up of the universe. Some commentators have called it the "God particle" for its role in turning the Big Bang into an ordered cosmos.
Higgs' and Englert's work shows how elementary particles inside atoms gain mass by interacting with an invisible field pervading all of space — and the more they interact, the heavier they become. The particle associated with the field is the Higgs boson.
"Without some kind of Higgs-like field, there really wouldn't be a universe at all," said Nicholas Hadley, a Maryland physics professor and chair of the U.S. collaboration board for one of the Higgs project's teams, in a statement.
"Because the particles would have no mass, and if everything were massless, there wouldn't be atoms, there wouldn't be planets, there wouldn't be stars and there wouldn't be people," he said. "The great question has been, did Higgs and Englert get it right with their particular model? And now it appears the answer is yes."
The Royal Swedish Academy of Sciences said the prize went to Higgs and Englert for work fundamental to describing how the universe is constructed.
"According to the Standard Model, everything, from flowers and people to stars and planets, consists of just a few building blocks: matter particles."
Gritsan said scientists continue their work to better understand the mysteries of the universe. There could, for example, be "brother" and "sister" particles.
Asked how it felt to be a Nobel winner, Englert told reporters by phone link to Stockholm: "You may imagine that this is not very unpleasant, of course. I am very, very happy to have the recognition of this extraordinary award."
CERN Director General Rolf Heuer said he was "thrilled" that the Nobel prize had gone to particle physics. He said the discovery of the Higgs boson at CERN last year marked "the culmination of decades of intellectual effort by many people around the world."
Some physicists were surprised that there was no recognition for the CERN teams that discovered the new particle, since there had been speculation of a prize for CERN as an institution.
The will of Alfred Nobel, the Swedish millionaire who invented dynamite, limits the award to a maximum of three people, harking back to an earlier era when science was conducted by individuals or very small teams.
Baltimore Sun reporter Meredith Cohn and Reuters contributed to this article
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