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New Fundamental Physics? Unexplainable Phenomena From Large Hadron Collider Experiment

Results announced by the LHCb experiment at CERN have revealed further hints for phenomena that cannot be explained by our current theory of fundamental physics.

A typical LHCb event fully reconstructed. Particles identified as pions, kaon, etc. are shown in different colors. Credit: CERN, LHCb Collaboration

In March 2020, the same experiment released evidence of particles breaking one of the core principles of the Standard Model – our best theory of particles and forces – suggesting the possible existence of new fundamental particles and forces.

Now, further measurements by physicists at Cambridge’s Cavendish Laboratory have found similar effects, boosting the case for new physics.

The Standard Model describes all the known particles that make up the universe and the forces that they interact through. It has passed every experimental test to date, and yet physicists know it must be incomplete. It does not include the force of gravity, nor can it account for how matter was produced during the Big Bang, and contains no particle that could explain the mysterious dark matter that astronomy tells us is five times more abundant than the stuff that makes up the visible world around us.

As a result, physicists have long been hunting for signs of physics beyond the Standard Model that might help us to address some of these mysteries.

One of the best ways to search for new particles and forces is to study particles known as beauty quarks. These are exotic cousins of the up and down quarks that make up the nucleus of every atom.

Beauty quarks don’t exist in large numbers in the world around as they are incredibly short-lived – surviving on average for just a trillionth of a second before transforming or decaying into other particles. However, billions of beauty quarks are produced every year by CERN’s giant particle accelerator, the Large Hadron Collider, which are recorded by a purpose-built detector called LHCb.

The way beauty quarks decay can be influenced by the existence of undiscovered forces or particles. In March, a team of physicists at LHCb released results showing evidence that beauty quarks were decaying into particles called muons less often than to their lighter cousins, electrons. This is impossible to explain in the Standard Model, which treats electrons and muons identically, apart from the fact that electrons are around 200 times lighter than muons. As a result, beauty quarks ought to decay into muons and electrons at equal rates. Instead, the physicists at LHCb found that the muon decay was only happening around 85% as often as the electron decay.

The difference between the LHCb result and the Standard Model was about three units of experimental error, or ‘3 sigma’ as it is known in particle physics. This means there is only around a one in a thousand chance of the result being caused by a statistical fluke.

READ MORE: https://scitechdaily.com/new-fundamental-physics-unexplainable-phenomena-from-large-hadron-collider-experiment/