More data needed to confirm if its Higgs boson; Indian researchers played a major role in the discovery of the elusive particle
Scientists with the European Organisation for Nuclear Research (CERN) say they have discovered a new subatomic particle that is consistent with the long-sought after Higgs boson, popularly known as the “God particle”. The elusive particle is believed to help all matter in the universe acquire mass. The Higgs particle has been the subject of a decades-old hunt after it was first postulated in the 1960s.
“We have reached a milestone in our understanding of nature,” said Rolf Heuer, director general of CERN, at a press conference in Geneva. “The discovery of a particle, consistent with the Higgs, opens the way to more detailed studies, requiring larger statistics, which will pin down the new particle’s properties, and is likely to shed light on other mysteries of our universe,” he added.
While the world remains abuzz about the discovery, for India, the finding holds special significance. The Higgs boson finding was aided by researchers from Delhi University, Bhabha Atomic Research Centre, Panjab University, Tata Institute of Fundamental Research (TIFR) and Saha Institute of Nuclear Physics (SINP). Naba K Mondal, senior professor at the department of high energy physics with TIFR says, “India has contributed in two major ways—providing instrumentation for the experiment and human resource for data analysis.” Many significant parts of the CMS experiment, one of the two experiments on the Higgs boson (the other is ATLAS), were built by TIFR. Furthermore, a number of theorists from India are constantly looking at the data generated, making sense of it and publishing papers to advance knowledge in the field. TIFR alone has fielded some 10 researchers in the CMS experiment.
Sukalyan Chattopadhyay, professor at SINP, says numbers do not give a complete picture of India’s role in the landmark findings. Chattopadhyay, who is India’s project leader for another experiment—ALICE—at CERN, says SINP played a big role in understanding the mechanics of the detectors of the CMS experiment. “Out of some 3,000 physicists at CMS, around 60 are from India. While this may be a small number, it doesn’t tell the entire story,” he says. “We’ve not only played a major role in providing hardware for the experiments, but also providing huge help with data analytics,” Chattopadhyay says.
If scientists can prove the presence of the subatomic particles (particles smaller than even the atom), it would greatly enhance our understanding of how the universe works. The Standard Model of Particle Physics explains how particles and various forces interact inside the universe, but does not provide any explanation on how particles acquire mass.
To explain the gaping hole in the model, English physicist Peter Higgs and others proposed the theory of the Higgs Field. Right after the Big Bang, the mega astronomical event that purportedly created the universe, the particles that were created had no mass, probably because of the extremely high temperature. However, as the universe evolved and cooled down, a Higgs Field was created which contained the Higgs boson particles. When particles enter this field, they attract Higgs bosons around them and gain mass.
Efforts at the Large Hadron Collider (LHC) have been underway for the past few years to find the Higgs boson. As the particle is short-lived, it is difficult to detect it. The experimental physicists at LHC, essentially a 27-km tunnel, 175m deep underground along the French-Swiss border, are trying to simulate conditions just after the Bing Bang in this tunnel, in the hope of seeing the Higgs bosons.
In December last year, CERN had revealed that results from their experiments had “tantalising hints” as to the evidence of the Higgs boson, but that more data and research was needed to confirm its presence.
How important is the discovery
Rarely are many of us excited about fundamental questions about the universe. However, the Higgs boson, perhaps because of its catchier nickname—God’s particle—has created an unprecedented buzz among laymen. So is this a finding as great as Albert Einstein’s theory of relativity or quantum mechanics? The question garners mixed response from eminent scientists. Famous British particle physicist Tom Kibble, who is professor of theoretical physics at Imperial College in the UK, says, “This would be a major discovery and an important milestone for the development of our theory of fundamental physics. But I would not rank it at the same level as the discovery of relativity or quantum mechanics.” Mark Wise, theoretical physicist at Caltech, agrees. “The theory of relativity or Newton’s Law were paradigm shifts. This is unlikely to be that so I wouldn't put it in that league,” he says.
Scientists who are more closely involved with the experiment at CERN take a different view. University of California-Davis theorist, John Gunion, who played a key role in designing the multi-million dollar detectors of LHC that would catch the glimpse of the boson, says, “Yes, it is of the same rank. Discovery of the Higgs boson confirms the mechanism by which all elementary particles (such as the electron and the quarks) acquire mass. Without mass the universe would not have formed, there would be no life, there would be no electronics, etc. It would not have been possible to formulate the theory of relativity!”
John Hopkins professor Andrei Gristan, an experimental physicist closely associated with the CMS experiment at CERN, says, “Such a discovery would be in the same league with some of the most fundamental and important discoveries of the past century. There has been probably none like this in the 21st century yet.”
But while a new particle has been confirmed, it will take time to establish that its characteristics are similar to the Higgs boson. CERN said current results are preliminary, and more data analysis is needed to confirm it’s the boson.
“We observe in our data clear signs of a new particle. The outstanding performance of the Large Hadron Collider and ATLAS and the huge efforts of many people have brought us to this exciting stage,” said Fabiola Gianotti spokesperson of the ATLAS experiment. “But a little more time is needed to prepare these results for publication,” Gianotti added.