The machine that could revolutionise physics

Will the Universe reveal a big secret? Deep underground in the Alps, scientists are barely able to contain their excitement about the world's most advanced particle accelerator. "It's an exciting time," says Dr Marcella Bona. "We are ready." She is 100 metres underground in the biggest machine ever built. The Large Hadron Collider (LHC) fires photons around a 27km tunnel close to the speed of light. They smash together to reveal the secrets of the Universe. The LHC has been made more powerful and restarts this month. Quantum physics is the study of the tiny particles that make up atoms. The Standard Model explains how three forces affect them: electromagnetism, weak and strong force. But the model does not explain gravity, the fourth force. And it cannot make sense of the mysterious dark matter and dark energy in the Universe. Scientists hope the upgraded LHC will find new particles and a fifth force of nature. This want to discover a "theory of everything". A US collider has reported results that don't fit the Standard Model. The LHC has measured strange behaviour in quarks. Both suggest scientists are close to something big. "There could be a revolution coming," says physicist Mitesh Patel. But scientists need to do more experiments. Ten years after finding the Higgs boson, the world is still waiting for the scientific revolution. "It's disappointing," says physicist Sabine Hossenfelder. She says that predictions are only "guesswork" and the LHC is a waste of money. Could it also be dangerous? Headlines warn it could create a black hole that will swallow the Earth. Scientists think this is impossible. If the LHC did make a mini black hole, CERN says it would vanish almost instantly. The stakes are high as Dr Sam Harper waits for the first results of the supercharged LHC. "This would upend the field. It would be the biggest discovery in particle physics since, since…" He is at a loss for words. His excitement is clear. Will the Universe reveal a big secret? Feel the force Yes: Science is on the brink of something big. These giant colliders are throwing out results that current theories can't explain. The next few years will be an exciting time for physics.