Large Hadron Collider Explained

Inside the Large Hadron Collider: Why We Smash Protons to Understand the Universe

Why humanity built a 27-kilometre machine to smash protons together - what it has taught us, what it has not found, and why physicists are rebuilding it now

The Large Hadron Collider is the world’s most powerful particle accelerator, built to probe the smallest known components of matter and recreate conditions that existed fractions of a second after the Big Bang.

Location	CERN, beneath the France-Switzerland border near Geneva
Main ring	26.7 km in circumference
What it collides	Mostly protons; also heavy ions such as lead, oxygen and neon
Run 3 collision energy	13.6 TeV for proton-proton collisions
Operating temperature	About 1.9 K (-271.3°C) for the main superconducting magnets
Current status	Run 3 ended in June 2026; Long Shutdown 3 is under way
Next phase	High-Luminosity LHC, planned to begin around 2030

About 100 metres beneath fields, roads and villages near Geneva, two beams of protons spent years racing in opposite directions through a tunnel almost 27 kilometres long. They moved so close to the speed of light that each proton could circle the machine more than 11,000 times a second. At four points around the ring, scientists deliberately steered the beams into one another and studied the debris.

That machine is the Large Hadron Collider, or LHC: the largest and most powerful particle collider ever built. Its basic idea is almost disarmingly simple. Create extremely energetic collisions, record what comes out, and use those traces to work backwards toward the rules that govern matter.

The questions behind it are anything but simple. What gives elementary particles mass? Why did matter survive when the early Universe also produced antimatter? What was matter like when the Universe was only microseconds old? And where should physicists look next if the Standard Model - our best theory of particles and forces - is not the whole story?

The timing makes those questions especially interesting. The LHC's Run 3 physics programme ended in June 2026, and the collider is now in Long Shutdown 3. Over the next few years, CERN will replace and upgrade major parts of the accelerator and its detectors before the machine returns around 2030 as the High-Luminosity LHC. The goal is not simply to make protons faster. It is to give rare events many more chances to happen.

So What Exactly Is a Hadron Collider?

The name sounds more forbidding than the idea. Break it into three pieces and most of the mystery disappears.

“Large” is literal: the main ring is 26.7 kilometres around. A “hadron” is a particle made of quarks; protons and neutrons are familiar examples. And a “collider” accelerates two beams in opposite directions and brings them together head-on.

Most LHC runs use protons, the positively charged particles found in atomic nuclei. CERN can also accelerate atomic nuclei themselves - especially lead, and more recently lighter ions such as oxygen and neon - when physicists want to study matter under very different conditions.

One misconception is worth clearing up early. The LHC does not normally smash complete atoms together like microscopic billiard balls. CERN starts with hydrogen, removes the electron, and sends the remaining proton through a whole chain of accelerators before it ever reaches the main ring.

Why Does Smashing Particles Together Teach Us Anything?

Imagine finding a sealed machine from another civilisation. You cannot take it apart, but you can fire tiny projectiles at it and measure how they scatter. The pattern would tell you something about what is hidden inside. Particle physics has used the same logic for more than a century: probe matter, measure the aftermath, then reconstruct the unseen structure.

That strategy helped reveal that atoms contain nuclei, that nuclei contain protons and neutrons, and that protons and neutrons are themselves built from quarks held together by gluons. The LHC takes that old experimental idea and pushes it to an extraordinary energy scale.

But high-energy collisions do more than break existing objects apart. They can create particles that were not present in the incoming beams. Einstein's E = mc² works in both directions: mass can be converted into energy, and concentrated energy can become mass.

That is why the LHC is better imagined as a microscopic particle factory than as a giant hammer. The Higgs boson was not sitting inside a proton waiting to be knocked loose. Energy from the collision produced it for an unimaginably short time; the Higgs then decayed, and scientists reconstructed it from the pattern left behind.

Almost Light Speed - So Why Add More Energy?

If the protons are already moving at almost the speed of light, a reasonable question follows: what is a stronger accelerator actually doing?

It is not making the protons dramatically faster. Special relativity forbids any particle with mass from reaching the speed of light. Near that limit, extra energy produces almost no noticeable gain in speed. Instead, it greatly increases the particle's energy and momentum.

During Run 3, proton-proton collisions reached 13.6 teraelectronvolts, or TeV, in centre-of-mass energy. The unit sounds intimidating, but the key idea is simple: on an everyday scale, the energy in one collision is tiny; on the scale of a proton, it is enormous. By concentrating that energy into a region much smaller than an atom, the LHC can produce rare processes and heavy particles that ordinary laboratory conditions cannot.

How a 27-Kilometre Collider Actually Works

No proton goes from a bottle of hydrogen to full LHC energy in one step. CERN uses a sequence of accelerators, each preparing the beam for the next. The electrons are stripped from hydrogen atoms, the protons are grouped into bunches, and those bunches are accelerated through several machines before being injected into the LHC.

Inside the main ring, radio-frequency cavities give the bunches precisely timed electrical pushes. A swing is a decent analogy: one well-timed push adds a little more energy on every pass. In the LHC, the timing is vastly more precise and the “swing” is a beam of particles circling thousands of times each second.

Magnets do the steering. Charged particles prefer to travel in straight lines, so powerful dipole magnets bend the beams around the circular tunnel, while other magnets squeeze and correct them so two proton bunches can meet at exactly the right place.

The machine also lives at two extremes. The beam pipes are kept at ultrahigh vacuum so stray gas molecules do not interfere with the protons. The superconducting magnets, meanwhile, are cooled with helium to about 1.9 kelvin - roughly -271.3°C, colder than the 2.7-kelvin cosmic microwave background that fills the Universe.

So kilometres of hardware sit colder than deep space while, for fleeting moments in some collisions, tiny regions become hotter than the centre of a star. The LHC is not just big; it is an exercise in maintaining several absurd physical conditions at once.

What Actually Collides?

The cartoon version shows two hard little proton balls smashing together. A real proton is nothing like that. It is a quantum object containing three valence quarks immersed in a restless sea of gluons and short-lived quark-antiquark pairs.

In a proton-proton collision, it is usually individual quarks or gluons inside the protons that actually interact. Their energy may create new particles, those particles may decay almost instantly, and the result can be a complicated spray of tracks and energy deposits through the detector.

The physicists' job is therefore a kind of forensic reconstruction. The short-lived particle is often gone before it could ever be “seen”. What remains is the debris, and the question is whether one hidden chain of events explains it better than all the alternatives.

Four Giant Detectors, Four Different Jobs

The accelerator makes the collisions. The detectors make the discoveries.

ATLAS and CMS are giant general-purpose experiments built to attack many of the same questions with different technologies. That duplication is deliberate: if two independent detectors using different hardware and analyses see the same signal, a detector-specific mistake becomes much less plausible.

ALICE has a different speciality: heavy-ion collisions and quark-gluon plasma. LHCb focuses on particles containing beauty and charm quarks, which makes it exceptionally sensitive to small differences between matter and antimatter.

All four are less like cameras than layered measuring machines. Inner systems trace charged particles, calorimeters measure energy, magnetic fields bend tracks so momentum can be calculated, and outer detectors identify particles such as muons that can travel through a great deal of material.

The harder problem is deciding what to save. The LHC produces far more collisions than researchers could ever store in full. Trigger systems make decisions in real time, rejecting ordinary events and keeping the tiny fraction most likely to contain useful physics. In the high-luminosity era, that filtering problem becomes harder still because many collisions will overlap in the detector at the same moment.

Detectors such as ATLAS and CMS surround the collision point with multiple layers of sensors. Scientists reconstruct what happened from the paths, energies and identities of the particles produced in each collision.

How We Got to a 27-Kilometre Collider

The LHC can look like a one-off technological monster, but it is really the latest link in a long chain of machines built to ask the same question at smaller and smaller scales: what is matter made of?

From radioactive sources to accelerators

Early nuclear physicists had to work with particles emitted naturally by radioactive materials. That was enough for Ernest Rutherford's experiments to reveal the atomic nucleus, but nature chose the particles' energies for them. To probe deeper, physicists needed sources they could control.

The twentieth century brought cyclotrons, synchrotrons and eventually colliders. Each generation offered higher energies, cleaner beams and more capable detectors. The broad logic has remained remarkably stable: finer structure and heavier particles generally demand more energetic experiments.

CERN and the road to the LHC

CERN was founded in 1954. Its first accelerator, the 600-MeV Synchrocyclotron, came into operation in 1957. Later machines became far more powerful, including the Proton Synchrotron and the Super Proton Synchrotron, or SPS.

The SPS later became central to one of CERN's landmark achievements: the 1983 discoveries of the W and Z bosons, carriers of the weak interaction. Carlo Rubbia and Simon van der Meer received the 1984 Nobel Prize in Physics for crucial contributions to that programme.

LEP: the collider that left the LHC its tunnel

Before the LHC, the same tunnel housed the Large Electron-Positron Collider, or LEP. From 1989 to 2000, LEP became a precision laboratory for the Standard Model. Among other achievements, measurements of the Z boson showed that there are three light neutrino families.

Electron-positron collisions are unusually clean because electrons and positrons are elementary particles. The drawback is that electrons radiate away large amounts of energy when forced around a circular path at very high energy. Protons are about 1,800 times heavier, so they lose far less energy that way and can be pushed to much higher energies in the same ring.

Scientists began discussing the LHC while LEP was still being designed. CERN formally approved the LHC in December 1994. LEP shut down in 2000, was dismantled, and the tunnel was prepared for the new proton collider.

2008: A Rough Start

On 10 September 2008, the first beam completed a full circuit of the LHC. After decades of planning and construction, the world's new flagship collider was finally alive. Nine days later, a major technical failure stopped it.

A faulty electrical connection between superconducting magnets triggered a helium release and damaged a section of the machine. No one was injured, but repairs and safety improvements kept the LHC out of operation for more than a year. Beams returned in November 2009.

The failure is more than a historical footnote. It is a reminder that the LHC is not one experiment but a tightly coupled engineering system: magnets, cryogenics, power supplies, vacuum equipment, electronics and protection systems all have to work together, often close to their technical limits.

2012: The Higgs Arrives

The LHC began sustained high-energy physics in 2010. Two years later came the result that would define the machine for the wider public.

On 4 July 2012, the ATLAS and CMS collaborations independently announced a new particle with a mass near 125 GeV. Both signals reached the five-sigma benchmark particle physicists use before claiming a discovery. In plain English, the result was far too strong to dismiss as ordinary statistical noise.

Later measurements showed that the new particle behaved as the Higgs boson predicted by the Standard Model. The discovery confirmed the central idea behind a mechanism developed in the 1960s by François Englert, Robert Brout, Peter Higgs and others to explain why some elementary particles are massive.

The Higgs boson appears only for an incredibly short time. Physicists do not observe it directly; they identify it statistically by studying the particles into which it decays.

The Higgs Without the “God Particle” Hype

The nickname “God particle” was catchy enough to survive for decades and misleading enough that many physicists still dislike it. The real physics needs no mysticism.

Modern particle physics describes nature in terms of quantum fields. What we call a particle is, roughly speaking, a detectable excitation of one of those fields. An electron is associated with the electron field; a photon with the electromagnetic field; the Higgs boson with the Higgs field.

The Higgs field has a non-zero value even in empty space. Different elementary particles couple to it with different strengths, and that coupling is tied to their masses. The top quark couples strongly and is heavy; the electron couples much more weakly and is light. This is not friction - particles are not literally wading through cosmic syrup - but a property built into the equations that describe them.

There is an important catch. Saying that the Higgs “gives everything mass” is wrong. The Higgs mechanism accounts for the masses of elementary particles such as quarks and charged leptons, and for the W and Z bosons. But most of the mass in a proton or neutron comes from the energy of the strong interaction binding quarks and gluons together. In other words, most of the mass in your body does not come directly from the Higgs field.

Finding the Higgs therefore closed one famous search and opened another. Physicists now want to measure how precisely it interacts with other particles, whether it can decay into unseen states, how it interacts with itself, and whether it offers a doorway to physics beyond the Standard Model.

The Discoveries Beyond the Higgs

A stranger zoo of matter

The Higgs remains the only new elementary particle discovered at the LHC. But it is hardly the only new particle. By late 2025, CERN counted roughly 80 particles discovered at the LHC, most of them hadrons - composite particles built from quarks.

Some fit the familiar categories of mesons and baryons. Others are exotic hadrons: states involving four quarks, called tetraquarks, or five, called pentaquarks. Exactly how those quarks are arranged is still an active question. Some states may be compact multiquark objects; others may behave more like loose “molecules” made from ordinary hadrons.

Why care about such an obscure zoo? Because the strong force is easy to write down and notoriously difficult to solve in the regime where quarks assemble themselves into visible matter. Every unusual hadron gives physicists another test case for understanding how that force really works.

Matter and antimatter are not perfect mirror images

The observable Universe is overwhelmingly made of matter, and that is a problem our current theories do not fully explain. In the hot early Universe, matter and antimatter were produced together; if they had remained perfectly balanced, most of both would have annihilated. Something tipped the balance.

One clue is CP violation - a small difference in how certain processes occur for matter and antimatter. In 2025, LHCb reported the first observation of CP violation in baryon decays, using beauty baryons and their antimatter counterparts. The effect passed the five-sigma discovery benchmark and opened a new way to test where nature's matter-antimatter asymmetry comes from.

It is not the full answer. The CP violation contained in the Standard Model appears far too small to explain the cosmic imbalance on its own. But every new place where the effect can be measured gives physicists another chance to test that conclusion.

Recreating matter from the young Universe

When heavy nuclei collide at the LHC, the energy density can become so high that protons and neutrons effectively melt into a quark-gluon plasma. In this state, quarks and gluons are no longer confined inside individual hadrons in the ordinary way. Physicists think similar matter filled the Universe during its first microseconds.

ALICE was built to study that plasma, but the story has become stranger with time. Results reported in 2026 strengthened evidence that collective, fluid-like behaviour can emerge in collision systems much smaller than researchers once expected. Proton, oxygen and neon collisions are now helping physicists ask how small a system can become and still behave like a tiny droplet of strongly interacting matter.

The LHC does not recreate the Big Bang. It cannot reproduce an expanding Universe or everything that happened at that moment. What it can do is recreate, for a fraction of a second in a microscopic volume, some of the temperatures and densities that existed when the Universe was very young.

Heavy-ion collisions at the LHC can briefly create quark-gluon plasma — an extreme state of matter thought to have filled the Universe during its first microseconds.

What the LHC Has Not Found

This part of the story matters as much as the headline discoveries, because experiments are also valuable when a plausible prediction fails.

Before the LHC switched on, many physicists hoped the Higgs would be followed by a whole new layer of particles. Supersymmetry, or SUSY, was one of the leading ideas. In many versions, every known particle has a heavier partner; some of those partners could also provide a dark-matter candidate.

No supersymmetric particle has been confirmed. Searches have instead pushed many simple SUSY scenarios into narrower and less accessible regions of parameter space. In 2026, ATLAS reported some of its strongest constraints yet. Supersymmetry is not “dead”, but the easiest versions are no longer where many physicists once hoped they would be.

Dark matter tells a similar story. Astronomical evidence that unseen mass shapes galaxies and galaxy clusters is overwhelming, yet the LHC has not found a confirmed dark-matter particle. Collider searches often look for an imbalance in momentum - a sign that something invisible may have escaped the detector - but so far they have produced limits, not a discovery.

That is not the same as learning nothing. A null result erases territory from the theoretical map. It tells researchers where new particles are not hiding and forces attractive ideas to survive increasingly difficult tests. Fundamental physics sometimes advances by closing doors.

About Those Black Holes

Before the LHC began operating, a small but highly visible public controversy claimed that its collisions might create dangerous black holes or other catastrophic states. The fears were taken seriously enough to be examined in detail, but the physics did not support a danger scenario.

The strongest reality check comes from nature itself. Cosmic rays have been producing collisions at energies beyond those relevant to individual LHC collisions for billions of years, on Earth and on astronomical bodies. If such interactions could trigger a runaway process capable of destroying ordinary matter, the continued existence of old stars and planets would be very difficult to reconcile with it.

Some speculative theories do allow microscopic black holes to be discussed mathematically, but any such objects produced at collider energies would be expected to decay almost immediately. None has been observed. CERN's safety reviews concluded that LHC collisions pose no danger to Earth.

Why Spend Billions on Questions With No Immediate Product?

There is no need to pretend that the LHC was built as a commercial technology programme. Its primary product is knowledge: a more accurate description of how nature works at its smallest scales.

The engineering spillovers are real, however. Building the collider has driven work in superconducting magnets, cryogenics, ultrahigh vacuum, radiation-hard electronics, detector technology, large-scale computing and data analysis. Related technologies have found applications in areas such as medical imaging, particle therapy and industrial instrumentation.

CERN's broader history is also a warning against demanding that fundamental research predict its practical return in advance. The World Wide Web, for example, was created at CERN to solve a communication problem for researchers. That does not mean every particle-physics project will produce another web. It means the useful consequences of ambitious research are often difficult to forecast at the moment the research begins.

There is a human return as well. LHC experiments train generations of physicists, engineers and software specialists inside collaborations that span institutions and countries. Many of those people eventually carry the methods - and the habit of solving unusually hard technical problems - into other fields.

The LHC's Second Life Begins in 2026

The LHC's Run 3 physics production finished on 14 June 2026, and the final beams were dumped later that month. CERN has now entered Long Shutdown 3, when the collider and its major experiments are being opened, rebuilt and upgraded. The current schedule targets the start of High-Luminosity LHC operations around June 2030.

“High luminosity” does not mean brighter beams in the everyday sense. In collider physics, luminosity measures how many opportunities particles have to collide. Increase the luminosity and you increase the number of useful events collected over time.

The reason is rarity. The most interesting process may happen only once in an enormous number of collisions. If you cannot raise the energy enough to open a completely new regime, another route is to collect vastly more data and improve the detectors until rare signals stop being rare in the dataset.

The HL-LHC is designed to deliver about ten times the integrated luminosity of the original LHC design. CERN estimates that over its lifetime it could produce roughly 380 million Higgs bosons. The Higgs would no longer be a particle physicists are simply happy to see; it would become a precision laboratory.

What Will the High-Luminosity LHC Hunt For?

Does the Higgs interact with itself?

One of the hardest targets is Higgs-pair production. The Standard Model predicts a particular shape for the Higgs field's energy landscape, and that picture implies that Higgs bosons can interact with one another. Measuring that self-interaction would help physicists test whether the Higgs sector really has the form the theory predicts.

The difficulty is rarity. Producing two Higgs bosons in the same event happens far less often than producing one. The current LHC dataset can constrain the process, but the much larger HL-LHC sample is expected to make the test far sharper.

Rare decays and tiny discrepancies

New physics may not announce itself with a spectacular new particle peak. It could first appear as something almost boring: a decay that happens slightly too often, a coupling that is a little weaker than predicted, or a rare process that should almost never occur.

That is the deeper value of more data at roughly similar collision energy. Precision can expose an unseen influence indirectly, much as a small wobble in an orbit can reveal an object that has not been observed directly.

Dark matter and other invisible particles

Searches for invisible particles will continue as well, including models in which the Higgs acts as a “portal” to a hidden sector. None of this comes with a guarantee. The upgrade simply gives nature many more chances to betray a tiny inconsistency.

Beyond the LHC: The Future Circular Collider

Even the upgraded LHC will eventually reach the end of its programme. Particle physics therefore has to plan decades ahead, because designing, funding and building machines at this scale takes a generation.

In May 2026, the updated European Strategy for Particle Physics recommended an electron-positron Future Circular Collider, FCC-ee, as the preferred option for CERN's next flagship collider after the LHC era. The same strategy kept completing and fully exploiting the HL-LHC as Europe's highest medium-term priority. CERN's 2026-2030 plan aims to be ready to seek Council approval for FCC-ee in 2028.

The proposed FCC would use a roughly 91-kilometre tunnel under France and Switzerland. Its first stage, FCC-ee, would collide electrons with positrons. Those particles are elementary, so the collisions are cleaner than proton collisions and can be measured with exceptional precision. The machine would act as a Higgs factory while also producing huge samples of Z and W bosons and top quarks.

A later proton-proton collider in the same tunnel, usually called FCC-hh, is envisioned as a much higher-energy successor. Its purpose would be different: not only precision, but direct exploration of energy scales the LHC cannot reach.

The distinction between proposal and approved project is crucial. As of 30 September 2026, the FCC has not been approved for construction. Public consultation processes in France and Switzerland are reaching their conclusion, and CERN's Member States are expected to consider whether to proceed around 2028. If approved and built, FCC-ee is envisaged to begin operation around the mid-2040s.

The High-Luminosity LHC will dramatically increase the amount of collision data available to physicists. Beyond it, CERN is studying the Future Circular Collider, a proposed machine with a tunnel roughly 90 kilometres in circumference.

Will a Bigger Collider Definitely Find New Physics?

No - and that is precisely why the question is scientific rather than engineering.

A new collider cannot promise a new particle in advance. If we already knew what it would find, the experiment would be confirmation rather than exploration.

What physicists can promise is a better test. An electron-positron collider could measure known particles, especially the Higgs, with precision the LHC cannot match. A future high-energy proton collider could reach directly into a new mass range. A discovery would rewrite part of physics; a clean non-discovery would still tell us that whatever explains dark matter, neutrino masses or other open problems is subtler, heavier or more weakly connected to known particles than many models assume.

That is the uncomfortable bargain at the frontier: the machine can be designed to ask a sharper question, but nature gets to choose the answer.

The Questions That Refuse to Go Away

The Standard Model is one of the most successful scientific theories ever built. It predicts an enormous range of measurements with astonishing accuracy. It is also obviously incomplete.

It has no particle that explains dark matter. It does not incorporate gravity as a quantum interaction. It does not explain the pattern of neutrino masses or why matter dominates over antimatter. And many of its numerical inputs - particle masses and interaction strengths - have to be measured rather than derived from a deeper principle.

The Higgs adds questions of its own. Why is its mass about 125 GeV? Why does the Higgs field have the value it does? Does it connect to particles we have not seen? And is the state of the Higgs field that fills our Universe absolutely stable, or only fantastically long-lived?

No collider can answer all of that by itself. But colliders can force some of these ideas to meet experiment, and that is the point. In fundamental physics, elegance is optional; surviving measurement is not.

One Last Analogy

Imagine trying to reconstruct the grammar of an unknown language from a damaged book. The Standard Model is a grammar that explains almost every surviving sentence astonishingly well. A collider lets us generate billions upon billions of new “sentences” and search for one that the grammar cannot explain.

Sometimes a missing word appears - as the Higgs did. Sometimes the grammar survives a more difficult test. Sometimes an attractive alternative rule fails. None of those outcomes is wasted if the experiment was sensitive enough to tell them apart.

Conclusion: A Machine Built to Ask Nature Directly

The Large Hadron Collider is usually introduced through superlatives: the world's largest collider, its most powerful accelerator, kilometres of magnets colder than space. They are impressive facts, but they are not the reason the machine matters.

What matters is the method. Humans have learned how to create microscopic conditions that do not normally exist around us, measure the aftermath with extraordinary precision and use those measurements to settle questions that argument alone cannot.

The LHC found the Higgs boson, but not the simple new world of supersymmetric particles many people hoped might follow. It created quark-gluon plasma, expanded the strange family of known hadrons and opened new measurements of matter-antimatter asymmetry. At the same time, it made the central puzzle sharper: the Standard Model works almost embarrassingly well, while the Universe still contains things the model cannot explain.

Now the collider is quiet. Magnets are warming, systems are being disconnected, detectors are open, and new hardware is going in. Around 2030, beams are expected to return to a machine built to collect far more data than before.

Perhaps the next surprise will be a new particle. Perhaps it will be a tiny deviation in the Higgs sector, a better picture of the early Universe, or another long list of ideas that nature refuses to cooperate with.

That uncertainty is not a flaw in the LHC. It is the entire reason to build an experiment at the edge of what we know.

FAQ

Is the Large Hadron Collider still operating in 2026?

LHC physics production ended in June 2026, and the collider is now in Long Shutdown 3 for maintenance and major upgrades. The High-Luminosity LHC is scheduled to begin operation around 2030.

What is the main purpose of the LHC?

The LHC tests the fundamental structure of matter by colliding high-energy particle beams and measuring what the collisions produce. Its programme includes precision Higgs physics, searches beyond the Standard Model, studies of matter-antimatter differences and research on quark-gluon plasma.

Did the LHC discover the Higgs boson?

Yes. ATLAS and CMS announced a new particle consistent with the Higgs boson on 4 July 2012. Later measurements established that its properties match the Higgs boson predicted by the Standard Model within current experimental precision.

Has the LHC found dark matter?

No confirmed dark-matter particle has been discovered at the LHC. Collider searches have instead placed increasingly strong limits on many possible models.

Can the LHC create a dangerous black hole?

No credible evidence indicates that LHC collisions pose such a danger. Natural cosmic-ray collisions have reached comparable or greater energies for billions of years. Hypothetical microscopic black holes in speculative models would be expected to decay essentially immediately, and none has been observed.

What is the next collider after the LHC?

CERN's 2026 European Strategy for Particle Physics recommends the proposed FCC-ee as the preferred next flagship collider. It is still a proposal, not an approved construction project; a decision is expected around 2028.