{"id":337,"date":"2026-03-31T20:54:16","date_gmt":"2026-03-31T19:54:16","guid":{"rendered":"https:\/\/entertainmentnews.site\/index.php\/2026\/03\/31\/a-once-fantastical-collider-could-answer-physics-biggest-mysteries\/"},"modified":"2026-03-31T20:54:18","modified_gmt":"2026-03-31T19:54:18","slug":"a-once-fantastical-collider-could-answer-physics-biggest-mysteries","status":"publish","type":"post","link":"https:\/\/entertainmentnews.site\/index.php\/2026\/03\/31\/a-once-fantastical-collider-could-answer-physics-biggest-mysteries\/","title":{"rendered":"A once-fantastical collider could answer physics\u2019 biggest mysteries"},"content":{"rendered":"
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The topic A once-fantastical collider could answer physics\u2019 biggest mysteries<\/strong> is currently the subject of lively discussion \u2014 readers and analysts are keeping a close eye on developments.<\/p>\n

This is taking place in a dynamic environment: companies\u2019 decisions and competitors\u2019 reactions can quickly change the picture.<\/p>\n

When it comes to particle physics, Tova Holmes has been there, done that and got the T-shirt \u2013 in fact, she designed the T-shirt herself. It all started back in 2022, when she and a few colleagues arrived at a meeting of particle physicists determined to make the case for developing an entirely new kind of particle-smashing machine.<\/p>\n

They did so by sporting tops emblazoned with a motif representing a circular particle accelerator and a single word: BUILD. \u201cWe wanted to find a way for people to visibly show how excited they were about a muon collider,\u201d says Holmes, who is based at the University of Tennessee, Knoxville.<\/p>\n

To its advocates, this newfangled collider would be exactly the shot in the arm that particle physics so desperately needs. The famous Large Hadron Collider (LHC) at the CERN particle physics laboratory near Geneva, Switzerland, wonderful as it is, simply hasn\u2019t delivered any truly new discoveries in years. The answer, say Holmes and her ilk, isn\u2019t to build ever-more powerful successors to the LHC, as some would like, but to change the game entirely. They want to collide together a strange type of particle known as the muon.<\/p>\n

We’ve discovered a door to a hidden part of reality \u2013 what’s inside?<\/p>\n

Physicists would dearly love to find new particles, but there’s no sign of them in colliders like the LHC. Now we have found a new way of accessing a tiny slice of reality where they might be hiding<\/p>\n

To many, though, the proposal has long seemed fanciful at best. After all, muons live for only a fraction of a second. But technological developments are now starting to make the idea more feasible \u2013 and funding organisations are eyeing it with serious interest. All of which makes it worth asking: what would it take to build this magnificent muon machine and, if we did, what secrets of reality might it reveal?<\/p>\n

In 2012, the LHC confirmed the existence of the Higgs boson, a particle proposed nearly half a century earlier to explain how the fundamental forces of nature first split in the early universe. The boson is produced by an excitation in the Higgs field, which endows certain particles with mass \u2013 including the W and Z bosons that carry the weak force \u2013 while leaving others, such as the photon, untouched.<\/p>\n

It was a spectacular vindication of physicists\u2019 theories about the world of particles. But it was also unsettling. The Higgs boson\u2019s own mass is puzzlingly small. Quantum field theory suggests it should be far larger, yet it perches, unnaturally balanced, at precisely the level required to keep the vacuum of space-time stable. Why so perfectly poised? \u201cPeople talk about the Higgs discovery as the completion of particle physics,\u201d says Patrick Meade at Stony Brook University in New York state. \u201cBut it was really the most confusing answer. It was the start.\u201d<\/p>\n

But if it was indeed the start, then the engine seems to have stalled, because today experimental particle physics is at an impasse. Answering the profound questions raised by the Higgs will require a new machine, one capable of probing deeper into nature\u2019s foundations through different or more powerful particle collisions.<\/p>\n

The most straightforward idea is the brute-force approach: build a bigger version of the LHC. That\u2019s the thinking behind the Future Circular Collider, a proposal being developed at CERN for a next-generation proton supercollider with a ring three to four times the circumference of the LHC. It could smash protons at over seven times the energy of its predecessor simply by stretching over a greater distance. This would allow physicists to discover particles or phenomena that emerge only at higher energies, while also probing ever-shorter distances and revealing more fundamental structures of matter.<\/p>\n

But protons aren\u2019t fundamental particles; they are bundles of quarks and gluons. When two protons meet head-on, it is their constituents that actually collide, producing messy sprays of secondary particles that physicists must painstakingly analyse. Plus, making a machine like the LHC any bigger would also come with an eye-watering price tag.<\/p>\n

The Large Hadron Collider at CERN in Geneva, Switzerland, will have its final data-taking run in 2026. What will take its place?D-VISIONS\/Shutterstock<\/p>\n

The Large Hadron Collider at CERN in Geneva, Switzerland, will have its final data-taking run in 2026. What will take its place?<\/p>\n

At the other extreme are electron-positron colliders, like the Compact Linear Collider, another proposal from CERN researchers. Electrons and positrons are fundamental, point-like particles with opposite charges, so their collisions are far cleaner and easier to interpret. The difficulty is that pushing them around a circular track at high energies causes them to shed energy copiously in the form of radiation. Linear colliders attempt to sidestep this limitation by accelerating particles along a straight track. But particles can\u2019t be reused, unlike in a ring, which recycles them in multiple passes.<\/p>\n

But there is also a dark horse in the running, in the form of the muon collider. Muons are essentially the heavier cousins of electrons, about 200 times more massive but with the same negative charge. You wouldn\u2019t be able to see them in the atoms that make up everyday matter, but they are produced fleetingly when high-energy cosmic rays strike molecules in Earth\u2019s upper atmosphere.<\/p>\n

Their extra heft means they radiate far less energy when bent around a ring in a collider, allowing them to reach much higher energies without requiring a vastly larger tunnel. Yet, like electrons, they are fundamental particles, so their collisions would be comparatively clean. In principle, a muon collider could push beyond our current energy frontier of 13.6 teraelectronvolts (TeV) by a factor of four while fitting inside a ring not much bigger than the LHC\u2019s, according to the data design studies by the US Muon Collider Collaboration.<\/p>\n

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The ‘impossible’ particle hinting at the universe’s biggest secrets<\/p>\n

Neutrinos have always been hard to explain \u2013 and now the detection of one so energetic it shouldn’t exist may help illuminate the strangest corners of the cosmos<\/p>\n

The idea isn\u2019t new. Physicists were already sketching proposals for muon colliders in the 1960s, but there was a catch: muons, unlike protons or electrons, have to be produced. Scientists can\u2019t gently pluck them from atoms before accelerating them to near-light speeds. Instead, they make them by smashing protons into a target, like a solid block of graphite, and producing showers of other particles called pions, which then decay into muons. The result is less a beam and more a spray \u2013 particles fanning out in all directions, with a wide range of energies and trajectories. Turning that chaos into a tightly focused, well-behaved beam is the central technical challenge.<\/p>\n

There is a further complication: muons are unstable. At rest, they survive for just 2.2 microseconds before decaying into other particles. By contrast, bringing protons in the LHC\u2019s main ring up to full speed takes around 20 minutes \u2013 roughly 550 million times longer than a muon\u2019s natural lifetime.<\/p>\n

\u201c
\n At some point, we need a new approach, and colliding muons may be that
\n \u201c<\/p>\n

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\n At some point, we need a new approach, and colliding muons may be that
\n \u201c<\/p>\n

A muon collider is, therefore, a race against time. Physicists must capture a chaotic cloud of newborn particles, then compress and accelerate it before it is too late. \u201cYou\u2019re starting with a beam of muons that\u2019s like the size of a beach ball, and you want to turn it into something the thickness of a human hair,\u201d says Meade. \u201cAnd you\u2019ve got to do it super, super fast.\u201d Then, two of these ultrathin beams must be steered towards so they collide directly, producing high-energy Higgs bosons in the splatter.<\/p>\n

For decades, that combination of speed and precision kept the idea on the sidelines. Muon colliders resurfaced during the 2013 Snowmass process, the once-a-decade strategy exercise in which US particle physicists map out the field\u2019s future priorities. Even then, they tabled the muon collider for being infeasible.<\/p>\n

Holmes was still early in her career at that time, working towards a master\u2019s degree. But over the following decade, a series of technical breakthroughs began to transform the muon collider into a serious contender for the discovery machine of her generation.<\/p>\n

One dramatic change has come about thanks to the gradual progress of the technologies. Early designs of the muon collider imagined modest collision energies compared with what researchers think we can achieve today. Recent plans push up to the 30 TeV range, 100 times more energetic than initial proposals in the 1960s. At those energies, muons travel so close to the speed of light that Albert Einstein\u2019s theory of special relativity becomes an ally. To an outside observer, time slows down for fast-moving particles. The faster the muons go, the longer they appear to live.<\/p>\n

The effect is dramatic. In even a modest 10-TeV muon collider, muons could survive for up to a tenth of a second, roughly 45,000 times longer than their ordinary lifetime. Paradoxically, making the muons go faster buys precious extra microseconds in which to control the beam.<\/p>\n

And researchers have learned to use that borrowed time. In 2020, the Muon Ionization Cooling Experiment, led by Kenneth Long at Imperial College London, demonstrated a technique known as ionisation cooling. Muons were passed through materials such as liquid hydrogen or lithium hydride, which reduced their momentum in all directions. The researchers then accelerated them forward using rapidly oscillating electric fields, transforming a diffuse spray into a tight, fast-moving bunch.<\/p>\n

CERN\u2019s detector records particle sprays from collisions in the Large Hadron Collider; the Higgs boson is identified via two muon pairs, seen here as red tracksCERN\/SCIENCE PHOTO LIBRARY<\/p>\n

CERN\u2019s detector records particle sprays from collisions in the Large Hadron Collider; the Higgs boson is identified via two muon pairs, seen here as red tracks<\/p>\n

\u201cIt sounds completely crazy because the back of the envelope just tells you that it\u2019s not possible,\u201d says Jesse Thaler at the Massachusetts Institute of technologies, who was sceptical at the thought of a muon collider a decade ago. \u201cBut actually, going beyond the back of the envelope, with more scientific study, it starts to look more and more plausible.\u201d<\/p>\n

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Researchers also, over time, gained practical experience with handling muons. Starting in 2017 at Fermilab in Illinois, the Muon g-2 experiment measured the minute wobble in muons circulating inside a magnetic field \u2013\u202fa quantity theorists had predicted with remarkable precision. Earlier measurements hinted that the value might deviate from the standard model of particle physics, our best understanding of how three of the four fundamental forces and elementary particles work, thus raising hopes of new physics. But improved calculations eventually brought the result back in line. Even so, the experiment provided hard-won expertise in producing, storing and controlling muons at scale.<\/p>\n

By 2022, when Holmes and her colleagues attended the next Snowmass meeting with her self-designed T-shirts, the muon collider had emerged as one of the leading candidates for the field\u2019s next major machine. In Europe, CERN-backed International Muon Collider Collaboration (IMCC) has begun parallel studies. In the US, many physicists would like to see a future muon collider built at Fermilab, while their European counterparts are exploring whether it could one day be hosted at CERN.<\/p>\n

\u201cThe muon collider is quite an old concept,\u201d says Steinar Stapnes at the University of Oslo in Norway, a member of the IMCC. \u201cNow, everybody thinks it is very interesting \u2014 scientifically and technically.\u201d<\/p>\n

We are at a point where it is anyone\u2019s game. Each collider proposal we\u2019ve mentioned must first complete technical studies and pilot demonstrations before governments decide which will secure billions in funding. In the meantime, rival camps of advocates will argue that their machine should define the next era of particle physics.<\/p>\n

\u201cA machine like this would be around the middle of the century,\u201d says Holmes. \u201cThat\u2019s if we get given a whole lot of funding.\u201d<\/p>\n

Sergo Jindariani, who heads the US Muon Collider Collaboration, is leading early feasibility studies for the proposed machine. \u201cWe\u2019ve been doing things the same way for many decades,\u201d he says. \u201cAt some point, we need a new approach, and colliding muons may be that.\u201d<\/p>\n

So what would a muon collider tell us if it were built? researchers note its central aim would be to probe the Higgs boson more deeply than any machine before it. Though it was discovered over a decade ago, the Higgs itself remains deeply baffling. \u201cIn the standard model, there are over a dozen particles, but none of them has properties like the Higgs. It\u2019s very unique,\u201d says Jindariani.<\/p>\n

Physicists suspect the Higgs field shaped the early universe. As the cosmos cooled after the big bang, the field switched on during a transition that split the unified electroweak force into the separate electromagnetic and weak forces we see today. How violent that transition was could help explain one of physics\u2019 deepest mysteries: why matter survived while antimatter vanished.<\/p>\n

Even today, the Higgs field may not be entirely stable. Some calculations even hint that our universe sits in a precarious state, with the Higgs field not at its lowest possible energy. In that case, a quantum fluctuation could one day tip it into a deeper energy state, a process known as vacuum decay. If this happened, everything about our universe would change instantly.<\/p>\n

We may live in a metastable \u201cbubble\u201d of the universe that could collapse if the Higgs field shifts to a lower-energy state, an event that would abruptly rewrite the laws of physicsBrooke Anderson Photography\/Getty Images<\/p>\n

We may live in a metastable \u201cbubble\u201d of the universe that could collapse if the Higgs field shifts to a lower-energy state, an event that would abruptly rewrite the laws of physics<\/p>\n

\u201cAll fundamental particles that have mass would get heavier, and presumably completely reorder our elements and cause total chaos,\u201d says Holmes.<\/p>\n

\u201cEssentially, it\u2019s like somebody turning the lights on or off in the universe. If they\u2019re off, none of us exists. If they\u2019re on, we can live,\u201d says Meade.<\/p>\n

Physicists already suspect that something is amiss. Quantum theory predicts that interactions with heavy particles should drive the Higgs boson\u2019s mass to enormous values. Instead, it sits at a relatively modest 125 gigaelectronvolts. Making the numbers work requires an extraordinary degree of fine-tuning.<\/p>\n

For decades, physicists have proposed ways to resolve this tension. One idea is that there is not one, but multiple Higgs bosons. If every known particle in the standard model, including the Higgs boson, has a heavier partner, it would cancel the effects that scientists currently think should inflate the Higgs\u2019s mass. Another idea is that the Higgs isn\u2019t fundamental at all, but composite \u2013 built from smaller constituents bound together, much like protons are made of quarks.<\/p>\n

A cataclysmic quantum fluctuation could wipe out everything at any moment. The fact that we\u2019re still here is revealing hidden cosmic realities<\/p>\n

Each of these possibilities would leave experimental fingerprints that a muon collider could detect by measuring how the Higgs couples with other particles and itself at high energies, says Holmes. It is this feature that advantages the muon collider over dedicated so-called Higgs factories \u2013 usually electron-positron colliders designed to produce vast numbers of Higgs bosons, but at lower energies than a muon machine could reach.<\/p>\n

Before a full-scale muon collider can be built, researchers must show that its key technologies work in practice. The next step is a demonstrator facility to test whether muon beams can be prepared and controlled well enough to collide. The IMCC is developing plans for such a machine at CERN, while the US Muon Collider Collaboration, working with the IMCC, is exploring a similar demonstrator at Fermilab. The goal is to produce detailed technical designs by around 2030. If approved and funded by governments, a demonstrator could begin operating in the early 2030s, providing the proof of principle needed for a full collider.<\/p>\n

But scientists like Holmes are in it for the long haul. She has faith that the muon collider will emerge victorious as the world\u2019s next great project. And physicists seem to be rallying around her. She and her colleagues are no longer the only ones wearing the muon collider T-shirts: \u201cI\u2019m delighted to see how often I show up at another department and see them already there.\u201d<\/p>\n