Physicists have discovered a potential flaw in a theory that explains how the building blocks of the Universe behave.
The standard model (SM) is the best theory to explain the fine-scale operation of the world around us.
But we have known for some time that the SM is a springboard for a more complete understanding of the cosmos.
Hints of unexpected behavior by a sub-atomic particle called the beauty quark can expose cracks in the foundation of this decades-old theory.
The findings are from data collected by researchers working at the Large Hadron Collider (LHC). It is a giant machine built in a 27 km long circular tunnel below the French-Swiss border. It breaks down beams of proton particles to investigate the limits of physics as we know it.
The mysterious behavior by the beauty quark may be the result of an as yet undiscovered sub-atomic particle exerting a force.
However, the physicists emphasize that more analysis and data are needed to confirm the results.
Dr Mitesh Patel, from Imperial College London, told BBC News: “We were actually shaking when we first looked at the results, we were so excited. Our hearts were beating a little faster.
“It’s too early to say if this is really a departure from the standard model, but the potential implications are that these results are the most exciting thing I’ve done in the field in 20 years. It’s been a long journey to to come here. “
There are building blocks of our world that are even smaller than the atom. Some of these sub-atomic particles are made up of even smaller constituents, while others cannot be broken down into anything else. The latter are known as fundamental particles.
The standard model describes all the known fundamental particles that make up the universe as well as the forces with which they interact.
But it cannot explain the greatest mysteries in modern physics, such as dark matter or the nature of gravity. Physicists know that it will eventually have to be replaced by a more advanced framework.
The Large Hadron Collider was built to discover physics outside the standard model. Therefore, if the results of LHCb are confirmed, it will be an important discovery.
The LHCb produces sub-atomic particles called “beauty quarks”, which do not usually occur in nature but are produced at the LHC. Sub-atomic particles undergo a process known as decay, where one particle changes into several, less massive ones.
According to the standard model, beauty quarks must decay in equal numbers of electron and moon particles. Instead, the process produces more electrons than muons.
One possible explanation is that an as yet undiscovered particle known as a lepto-quark was involved in the decay process and made it easier to produce electrons.
Dr Paula Alvarez Cartelle, of the University of Cambridge, was one of the scientific leaders behind the finding. She said: ‘This new result offers provocative hints of the presence of a new fundamental particle or force that otherwise interacts with these … particles.
“The more data we have, the stronger the result has become. This measurement is the most important in a series of LHCb results of the past decade that appear to be in line – and may all point to a general statement.
“The results have not changed, but their uncertainty has shrunk, increasing our ability to see possible differences with the standard model.”
In particle physics, the gold standard for a discovery is a level called five-sigma, in which the chance at one in 3.5 million is that the result is a stroke of luck.
The measurement from LHCb is three-sigma, which means that the chance at about one in 1000 that the measurement is statistically random. According to team leader, Prof Chris Parkes, of the University of Manchester, people should therefore not be carried away by these findings.
“We may be heading for a new era of physics, but if we do, we are still relatively early on that path at this stage. We have seen the results of this meaning come and go before, so we must be careful. be well excited, ‘he said.
But if confirmed by further analysis and data when the LHCb starts up again next year, it could be one of the biggest recent discoveries in physics, according to Dr Konstantinos Petridis of the University of Bristol.
“The discovery of a new force in nature is the holy grail of particle physics. Our current understanding of the constituents of the Universe falls remarkably short – we do not know what 95% of the Universe consists of or why there is such a thing.” a great imbalance between matter and anti-matter. “
The results were presented for publication in Nature Physics.
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