Â鶹ÒùÔº

Europe's plans for an even bigger particle collider, explained

Europe's physics lab CERN is planning to build a particle-smasher even bigger than its Large Hadron Collider to continue searching for answers to some of the universe's tiniest yet most profound mysteries.

The Future Circular Collider (FCC) has not yet received a political green light or funding. Even if approved, the vast project would not start operations until the 2040s—or be completed until the end of the century.

CERN's Large Hadron Collider (LHC), which famously discovered the "God particle" Higgs boson and is currently the world's powerful particle accelerator, is expected to have run its course by the 2040s.

These massive machines smash particles—such as protons which are inside every atom, or lead ions—into each other.

To do so, they use superconducting magnets to beam the particles at incredible speeds around giant underground rings, using detectors to capture the collisions.

This can expose new elementary particles of matter, revealing their true nature.

For example, in 2012 the LHC proved the existence of the Higgs boson, a long-theorized maker of mass known as the God particle. It is a key element of the standard model, which is our best understanding of how the universe works.

The LHC spins around a 27-kilometer tunnel deep under the border between France and Switzerland.

The future collider would be more than three times this size, stretching around 91 kilometers, also under the two countries.

That extra runway would allow it to smash particles into each other with eight times more energy.

It would also have far more sensitive detectors.

The hope is that this will allow the collider to discover lighter or heavier particles than the ones scientists already know about.

Bigger to see smaller

Other mysteries abound.

Scientists believe that normal matter—such as everything we can see—makes up just 5% of the universe.

The rest is thought to be dark matter and dark energy, the nature of which remains unknown.

Exactly what is going on with antimatter—the mysterious twins of visible matter—is another open question. The mass of super-light neutrino particles has also remained elusive.

CERN hopes that its future collider could finally shed some light on these quandaries.

A feasibility study is under way for the FCC, which CERN estimated earlier this year will cost around $17 billion.

If approved, the project would be in two separate phases.

An electron-positron collider would start smashing lighter particles together in 2046, aiming to further explore the physics of the Higgs boson.

Then the heavy duty proton-proton collider for heavier particles would come online in 2070.

Its energy target would be 100 trillion electronvolts—crushing the LHC's record of 13.6 trillion.

Work is scheduled to start in 2033 on a 5.5 meter-wide tunnel passing 100 meters under Lake Geneva in Switzerland, and looping round through a range of the French countryside.

There will be eight sites on the surface, seven of which will be in France.

Then from 2038, the scientific equipment would start getting installed.

The two main experiments will need huge underground caverns up to 66 meters tall to house the particle detectors.