Muons: 'Strong' evidence found for a new force of nature.

 

The findings come from the US Muon g-2 experiment.

From sticking a magnet on a fridge door to throwing a ball into a basketball hoop, the forces of physics are at play in every moment of our lives.

All of the forces we experience every day can be reduced to just four categories: gravity, electromagnetism, the strong force, and the weak force.

Now, physicists say they have found possible signs of a fifth fundamental force of nature.

The findings come from research carried out at a laboratory near Chicago.

The four fundamental forces govern how all the objects and particles in the universe interact with each other.

For example, gravity makes objects fall to the ground, and heavy objects behave as if they are glued to the floor.

The UK's Science and Technology Facilities Council (STFC) said the result "provides strong evidence for the existence of an undiscovered sub-atomic particle or new force".

But the results from the Muon g-2 experiment don't add up to a conclusive discovery yet.

There is currently a one in a 40,000 chance that the result could be a statistical fluke - equating to a statistical level of confidence described as 4.1 sigma.

A level of 5 sigma, or a one in 3.5 million chance of the observation being a coincidence, is needed to claim a discovery.

Prof Mark Lancaster, who is the UK lead for the experiment, told BBC News: "We have found the interaction of muons are not in agreement 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: "Clearly, this is very exciting because it potentially points to a future with new laws of physics, new particles and a new force which we have not seen to date."

The finding is the latest in a string of promising results from particle physics experiments in the US, Japan, and most recently from the Large Hadron Collider on the Swiss-French border.

The experiment, based at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, searches for signs of new phenomena in physics by studying the behavior of sub-atomic particles called muons.

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 can't be broken down into anything else (fundamental particles).

The muon is one of these fundamental particles; it's similar to the electron, but more than 200 times heavier.

The Muon g-2 experiment involves sending the particles around a 14-meter ring and then applying a magnetic field. Under the current laws of physics, encoded in the Standard Model, this should make the muons wobble at a certain rate.

Instead, the scientists found that muons wobbled at a faster rate than expected. This might be caused by a force of nature that's completely new to science.

No one yet knows what this potential new force does, other than influence muon particles.

Theoretical physicists believe that it might also be associated with an as-yet-undiscovered sub-atomic 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 at the LHCb experiment at the Large Hadron Collider described results that could point to a new particle and force.

Dr. Mitesh Patel, from Imperial College London, who was involved with that project, said: "The race is really on now to try and get one of these experiments to really get the proof that this really is something new. That will take more data and more measurements and hopefully show evidence that these effects are real."

Prof Allanach has given the possible fifth force various names in his theoretical models. Among them are the "flavor force", the "third family hyper force" and - most prosaic of all - "B minus L2".

In addition to the more familiar forces of gravity and electromagnetism (which is responsible for electricity and magnetism), the strong and weak forces govern the behavior of sub-atomic particles.

A fifth fundamental force might help explain some of the big puzzles about the Universe that have exercised scientists in recent decades.

For example, the observation that the expansion of the Universe was speeding up was attributed to a mysterious phenomenon known as dark energy. But some researchers have previously suggested it could be evidence of a fifth force.

Elon Musk's brain-chip company, Neuralink, released a video of a monkey playing video games with its mind.

 

The billionaire Elon Musk owns Neuralink, a company dedicated to making neural-interface technology.

Elon Musk finally got to show off his monkey.

Neuralink, a company founded by Musk that is developing artificial-intelligence-powered microchips to go in people's brains, released a video Thursday appearing to show a macaque using the tech to play video games, including "Pong."

Musk has boasted about Neuralink's tests on primates before, but this is the first time the company has put one on display. During a presentation in 2019, Musk said the company had enabled a monkey to "control a computer with its brain."

In August 2020 the company did a live demonstration of the technology in a pig named Gertrude.

Neuralink says the monkey, named Pager, had a chip implanted in his brain six weeks ago. In the video, he was given a joystick that was hooked up to a video game in which he moves a cursor to a colored square. When he successfully moves the cursor, he's given some banana smoothie through a tube.

While Pager uses the joystick, the Neuralink chip records his brain activity and sends it back to a computer for analysis of what his brain does when he moves his hand. The joystick is then unplugged from the machine, but the monkey continues to control the game, with brain signals being relayed by the Neuralink chips.

Theoretically, the same tech could be used to give people control of synthetic limbs via a Neuralink brain implant. In a tweet Thursday, Musk said the first Neuralink product would let people with paralysis control a smartphone.

Andrew Jackson, a neuroscience expert who is a professor at Newcastle University, told Insider that getting primates to control video games via neural interfaces was not new — comparable demonstrations were done in 2002 — but said it was a good test of the tech.

"If you invent a new telescope, it makes sense to first point it where you know what you will see," he said. "So they are following a very sensible route to validate their device. I am sure this device will contribute to new scientific discoveries in future (especially if they make it widely available to scientists), as well as improving the usability of existing neural interface technologies for people with paralysis."

Jackson added that the engineering of the device, being implanted wirelessly in Pager's skull, was a significant advance.

"What is definitely new and innovative is that there are no cables coming through the skin, and the brain signals are all being sent wirelessly," Jackson said. "This to me is the advance here, and is important both for improving the safety of human applications (wires through the skin are a potential route for infection) and also as a way of improving the welfare of animals used in neuroscience studies. The Neuralink team has definitely made progress in this regard."

Rylie Green, a bioengineering researcher at Imperial College London, also praised Pager's apparent welfare. "The best thing I can see from that video is that the macaque is freely moving," she said. "There's also no visible package connected to it. I would say that is definitely progress — not super innovative but a nice positive step forward."