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  • The year is 1998, and Dr. Chris Polly isgraduate student working at Brookhaven National  

  • Laboratory in Upton, New York. The facility  has just installed a new machine that is unlike  

  • anything he's ever seen before: The Alternating  Gradient Synchrotron, also known as the Muon g-2  

  • ring. It's a fourteen ton behemoth, featuringparticle accelerator capable of firing muon beams  

  • into a fifty-foot-wide storage ring. This ring is  essentially a racetrack for subatomic particles,  

  • using powerful superconductors to create  a magnetic field within. It's a piece of  

  • technology so delicate it needs to be kept at  negative 450 degrees Fahrenheit to even function.

  • The purpose of this machine is studying a kind of  particle known as a muon. Little does Polly know,  

  • it's with this very machine that he and his  team of physicists may be toppling mankind's  

  • most accurate set of laws for our universeThe Standard Model of Particle Physics.

  • How is such a thing even possible, and what does  any of this mean? Take a deep breath and hold on  

  • to your brain, because everything we thought  we knew about particle physics may be about to  

  • change. Our story starts all the way back in 1936,  with the discovery of the muon - a little-known  

  • particle outside of physics circles, but the  lynchpin of everything we'll be discussing today.

  • Cast your mind back to your physics class  in high school, and see if you can remember  

  • the structure of the atom: It's a nucleus  - formed out of protons - being orbited by  

  • electrons. Protons carry a positive electrical  charge, and electrons carry a negative charge.  

  • This refresher is important, because the  Muon is essentially a much larger version  

  • of the electron - around 207 times largerto be exact. It's so similar to an electron  

  • in a structural sense that some scientists even  refer to them asfat electrons”, and crucially,  

  • it's also an incredibly stable particle, meaning  it won't degrade as quickly as some others.

  • You have to bear in mind, though, that everything  we're discussing here is incomprehensibly small.  

  • Even the most stable particles  degrade within millionths of a second,  

  • which is why the development of incredibly  precise particle accelerators in the last  

  • few decades have been such a boon for  physicists trying to study our universe.

  • Looking through the lens of quantum mechanicswhich is to say, the laws of interaction between  

  • subatomic particles - the muons display some  interesting traits. Because of their negative  

  • charge, they have a tendency to display something  known as a Larmor precession - often colloquially  

  • referred to as a wobble - while placed inmagnetic field. The speed of this wobble can  

  • be used to calculate a muon's “magnetic moment”  - this is a value affected by the interactions  

  • of the muon with other subatomic particles. Think of it almost like a woman's husband coming  

  • home one night smelling of beer, cigarettes, and  perfume. You could probably estimate from this  

  • data point - i.e, the telltale smells - what  kind of people he's been rubbing elbows with.

  • As we mentioned earlier, a Muon is  functionally the same as an electron,  

  • except 207 times larger. Therefore, using what  we know about the electron and its properties  

  • from prior research, it should be easy to  factor in the size difference and figure  

  • out the particle's g-factor. The g-factorto use an extremely pared down definition,  

  • is the value that gives us insight  into the magnetic moment of a particle.

  • We can figure out the g-factor of a Muon by  judging how fast it wobbles while inside a  

  • magnetic field. Currently, we know that  the g-factor of a Muon is higher than 2,  

  • hence the designation g-2 - pronounced G minus 2,  because when the 2 is extracted, all that's left  

  • is the precise measurement of the magnetic moment  of a Muon. This equation has allowed scientists to  

  • come up with a prediction for what the exact  g-factor of a Muon is. Still with us? Good.

  • To make a prediction, scientists needtheoretical framework. And in this case,  

  • that framework is the Standard Model.

  • Thanks to the hard work of a hell of a lot of  physicists, we know that literally everything that  

  • exists is made of fundamental particles and driven  by fundamental forces. The question since then  

  • has been, “What are they?” Currently, there are  four known fundamental forces - the strong force,  

  • the weak force, the electromagnetic  force, and the gravitational force.  

  • The theory that has come the closest  to explaining three of the four forces,  

  • as well as all known fundamental  particles, is the Standard Model.

  • Physics is a complex field - it's perhaps the  broadest of all of the sciences. After all,  

  • it encompasses everything from the extreme microlike the subatomic particles we're discussing  

  • today, to the extreme macro, like the very  expanse of the universe itself. Because of the  

  • limits of technology, it's impossible to currently  understand the full totality of the quantum world.  

  • That's why physicists need to use our partial  knowledge to build theoretical frameworks which  

  • they can use to make educated assumptions about  the areas we don't have comprehensive data on yet.

  • The strength of a theory is tested on how  many of its assumptions are proved correct  

  • through experimentation, and what the theory gets  wrong tells us about the gaps in our knowledge,  

  • and where further research is needed.

  • This is the most important thing to understand  about what people mean when they saythe laws  

  • of physics.” These are not immutable  rules that govern universal action,  

  • engraved in stone on top of a mountain. The  laws of physics are a human construct designed  

  • to impose a sense of logic and understanding  on the nature and behaviour of the universe,  

  • from the subatomic to the cosmicWhen the laws of physics are broken,  

  • nothing about the universe fundamentally changes  - what shifts is our understanding of it.

  • In a sense, the laws of physics truly  are the laws that are meant to be broken,  

  • as most experiments in the field  are trying to do just that.

  • But, before we get to laws being broken, let's  take a look at the laws that the Standard Model  

  • of Particle Physics is laying down. As we  mentioned earlier, the Standard Model can  

  • explain the functions and interplay of three  of the fundamental forces of the universe:  

  • The strong force, the weak forceand the electromagnetic force,  

  • as well as corresponding carrier particles  exchanged during the transfer of energy,  

  • known as bosons. The Standard Model  also accounts for twelve different  

  • fundamental or elementary particles. These are  divided into two groups: Quarks and Leptons.

  • The quarks include the up quark, down quarkcharm quark, strange quark, top quark,  

  • and bottom quark. The Leptons include the  electron, electron neutrino, muon, muon neutrino,  

  • tau, and tau neutrino. You don't need to  know a huge amount about these two groups,  

  • but for the purposes of distinguishing  them, it's worth noting that they're  

  • subject to different fundamental forcesQuarks are subject to all four forces,  

  • but the Leptons are only subject to threehaving no connection to the strong force.

  • What gives the Standard Model such a foothold  in physics is how incredibly accurate  

  • its estimations have been. Not only has it pretty  much perfectly predicted the behaviour of a number  

  • of subatomic particles, it also predicted the  very existence of several phenomena - including  

  • the legendary Higgs Boson, also known as The  God Particle, discovered in 2012. However,  

  • there are still concepts that exist  outside the remit of the Standard Model,  

  • including anti-matter, dark matterand its biggest blindspot of all,  

  • the function of gravity in the quantum worldSo, it goes without saying that the Standard  

  • Model isn't perfect, but it's undeniably the best  set of laws for quantum physics we currently have.

  • Until, of course, the Muon experiments began.

  • We return to Dr. Chris Polly, back in 1998,  with his incredible Muon g-2 machine. As we  

  • said earlier, a theory is only as good as its  predictions, and if the subatomic universe  

  • really is comprised of six quarks, six leptonsand some bosons, then the Standard Model should  

  • be able to perfectly predict the g-factor ofMuon inside a magnetic field. But as Polly and  

  • his fellow physicists fired the Muon beam into  the field, preparing to time the speed of the  

  • resulting wobbles, they came to a startling  conclusion: The prediction for the g-factor  

  • under the Standard Model was way off, at least in  terms of the level of certainty to call something  

  • correctin physics. And as it's important  to remember, the g-factor and magnetic moment  

  • is affected by the kinds of particles and  forces that the Muon is interacting with.

  • If the team's hunch was right and this  result wasn't just some statistical fluke,  

  • this could only mean one thing: They just defied  our most accurate model for the quantum world.  

  • In other words, they just  broke the laws of physics.

  • But before they could replicate the experimentBrookhaven pulled the plug in 2001. It shouldn't  

  • be surprising that a 14 ton machine that  needs temperatures of negative 450 degrees  

  • fahrenheit to work costs a lot of money to  keep running. Dr. Polly was devastated - if  

  • he could prove this new discovery wasn't a  fluke, he'd be a shoo-in for a Nobel Prize.  

  • It'd change the very face of particle  physics. But he'd just lost his opportunity.  

  • His time would come again, but it  wouldn't be for another two decades.

  • Flash forward to 2018. Dr. Polly, now  a much more experienced physicist,  

  • was at the head of a new Muon research  division at the Fermi National Accelerator  

  • Laboratory in Batavia, Illinois. He got to  unite with an old friend: The Muon g-2 Ring,  

  • transported by barge and truck all the way from  Long Island so the long-awaited experiments could  

  • finally resume. At long last, he could revisit  the experiment that had haunted him for 20 years,  

  • and see if it was possible  to reproduce the results.

  • And according to the current data, it seems that  Dr. Polly's patience has been rewarded with the  

  • discovery of his career. A discovery that he  himself compared to landing a human on Mars  

  • for the particle physics world. The Fermi  team documented a Muon particle once again  

  • disobeying the laws of physics. The particles were  wobbling significantly too fast to comply with  

  • the predictions of the Standard Model, opening  up a bevy of wild possibilities. If the data,  

  • once again, isn't a fluke, then it potentially  implies that there are more fundamental  

  • particles out there than we'd previously  imagined. Some have even theorised that it  

  • could be a sign of a previously undocumented  fifth fundamental power acting on the Muons.

  • It's too early to go into any specifics on this. A  lot of the data collected in this latest round of  

  • experiments hasn't been properly processed, and  until then, there's still a 1 in 40,000 chance  

  • that this data could just be a statistical  anomaly. This may seem like an insignificant  

  • chance, but physics works on a very different  set of parameters to your daily life. Either way,  

  • these early leads are extremely promising, and  a lot of physicists are celebrating right now.

  • You may think it's counterintuitive to celebrate  further holes being pierced into the Standard  

  • Model, but mourning disproven theories has  never been how physicists roll. If the data  

  • continues to corroborate this new discoveryit means there are particles and potentially  

  • even fundamental forces out there, waiting to be  discovered. These areas will be like open oceans,  

  • to be sailed and explored by new generations of  physicists for decades or even centuries to come.  

  • Some people see physics as piles of boring mathor dusty old textbooks, but physics is actually  

  • the quest to truly understand the incredible  mystery that is the universe we live in.

  • And what's particularly amazing  about discoveries like this one  

  • is that it proves we're still only getting  started. The answers are out there,  

  • and it's up to the world's intrepid researchers  to explore, experiment, and find them - even if  

  • it means breaking a few laws along the wayAfter all, that's what physics is all about.

  • Now check outWhy Is There A Universe?”  andAstronomers Find Invisible Galaxies  

  • That Change Everything We Know About Science”  for more physics facts that'll blow your mind!

The year is 1998, and Dr. Chris Polly isgraduate student working at Brookhaven National  

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Scientists Just Broke Laws of Physics

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    Summer posted on 2021/05/07
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