Whether it’s sticking a magnet on a refrigerator door or throwing a ball into a basketball hoop, the forces of physics are at play every moment of our lives.
All the forces that we experience every day can be reduced to just four categories: gravity, electromagnetism, strong force, and weak force.
Now physicists say they have found possible signs of a fifth fundamental force in nature.
The results come from research conducted in a laboratory near Chicago.
The four fundamental forces govern how all objects and particles in the Universe interact with each other.
For example, gravity causes objects to fall to the ground, and heavy objects behave as if they are stuck to the ground.
The UK Science and Technology Facilities Council (STFC) said the result “provides strong evidence for the existence of an undiscovered subatomic particle or new force.”
But the results of the Muon g-2 experiment are not yet a conclusive discovery.
There is currently a one in 40,000 chance that the result will be a statistical chance – which is equivalent to a level of statistical confidence described as 4.1 sigma.
A 5 sigma level, or one in 3.5 million chance that the sighting is a coincidence, is needed to claim a discovery.
Professor Mark Lancaster, who is the UK responsible for the experiment, told BBC News: “We have found that the muon interaction does not agree with the Standard Model. [the current widely accepted theory to explain how the building blocks of the Universe behave]. “
The University of Manchester researcher added: “Obviously, this is very exciting as it potentially points to a future with new laws of physics, new particles and a new force that we haven’t seen in the future. this day.”
This discovery is the latest in a series of promising results from particle physics experiments in the United States, Japan and, more recently, the Large Hadron Collider at the Franco-Swiss border.
Professor Ben Allanach, University of Cambridge, who was not involved in the latest effort, said: “My sense of Spidey stings me and tells me this is going to be real.
“I’ve searched all my career for forces and particles beyond what we already know, and that’s it. This is the moment I was waiting for and I’m not getting much sleep because I’m too excited. “
The experiment, based at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, looks for signs of new phenomena in physics by studying the behavior of a subatomic particle called a muon.
There are building blocks of our world that are even smaller than the atom. Some of these subatomic particles are made up of even smaller constituents, while others cannot be broken down into anything else (fundamental particles).
The muon is one of these fundamental particles; it is similar to the electron, but over 200 times heavier.
The Muon g-2 experiment involves sending the particles around a 14-meter ring and then applying a magnetic field. According to current laws of physics, encoded in a theory known as the Standard Model, this should make muons wobble at a certain speed.
Instead, the scientists found that the muons were oscillating faster than expected. They say it could be caused by a force of nature that is completely new to science.
No one knows yet what this new potential force does, other than influencing muon particles.
Theoretical physicists believe that it could also be associated with a still unknown subatomic particle. There is more than one concept for what this hypothetical particle might be. One is called a leptoquark, another is the Z ‘boson (Z-prime boson).
Last month, physicists working on the LHCb experiment at the Large Hadron Collider described results that could point to a new particle and a new force.
Dr Mitesh Patel, from Imperial College London, who participated in the work of the LHC, said: “The race is really on now to try to get one of these experiments to really prove that it really is. something new. take more data and more measurements and hopefully show evidence that these effects are real. “
Professor Allanach has given the fifth possible force various names in his theoretical models. Among them are the “flavor force”, the “third hyperforce in the family” and – the most prosaic of all – “B minus L2”.
In addition to the more familiar forces of gravity and electromagnetism (responsible for electricity and magnetism), strong and weak forces govern the behavior of subatomic particles.
A fifth fundamental force could help explain some of the great puzzles about the Universe that have exercised scientists over the past decades.
For example, the observation of the accelerating expansion of the Universe has been attributed to a mysterious phenomenon known as dark energy. But some researchers have previously suggested that it could be evidence of a fifth force.
Dr Maggie Aderin-Pocock, co-host of the BBC’s Sky at Night show, told BBC News: “It’s pretty mind-boggling. It has the potential to turn physics around. We have a number of mysteries. that remain unresolved. And that could give us the key answers to solving these mysteries. “
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