CERN wants to go super-sized. The particle physics lab near Geneva in Switzerland has just unveiled its plans for a replacement for the Large Hadron Collider (LHC).

The news: CERN has released a design report for the Future Circular Collider, which would be four times as big as the LHC. Colliders send particles around a loop at incredible speeds and then let researchers analyze the fallout when they smash into one another. The design for the FCC would be some 100 kilometers (62 miles) long and, when operating at full capacity, collide particles at 10 times the energy of the LHC.

Why it’s needed: The LHC’s biggest success was the discovery of the Higgs boson, the once-theoretical particle that gives all matter its mass (this New York Times animation describes it brilliantly.) CERN physicists hope the FCC will let them probe the nature of the Higgs more closely. But it should also open the door to as-yet-unknown physics and help settle some big unanswered questions about our universe (such as what dark matter is made of and why there’s more matter than antimatter—we’ve no idea about either.) The biggest problem is that our Standard Model of physics really doesn’t explain the universe very well (it doesn’t explain gravity, for example.) But the LHC has so far failed to provide us with any hint of an alternative.

Pricey physics: The report for the FCC involved more than 1,300 contributors from 150 universities over the past five years.  If the collider gets the go-ahead, it could be up and running by 2040. It would cost an estimated €5 billion ($5.7 billion) to build the tunnel. A further €4 billion ($4.6 billion) would be needed for the first collider (designed to collide particles called leptons). Another €15 billion ($17 billion) would be required for the final collider that would smash protons together.

“The FCC conceptual design report is a remarkable accomplishment. It shows the tremendous potential of the FCC to improve our knowledge of fundamental physics and to advance many technologies with a broad impact on society,” CERN director-general Fabiola Gianotti said in a statement.