Mark Thomson, a professor of experimental particle physics at the University of Cambridge, has landed one of the most coveted jobs in global science. But it is hard not to wonder, when looked at from a certain angle, whether he has taken one for the team.<\/p>\n
On 1 January, Thomson takes over as the director general of Cern, the multi-Nobel prizewinning nuclear physics laboratory on the outskirts of Geneva. It is here, deep beneath the ground, that the Large Hadron Collider<\/a> (LHC), the largest scientific instrument ever built, recreates conditions that existed microseconds after the big bang.<\/p>\n The machine won its place in history for discovering the mysterious Higgs boson<\/a>, whose accompanying field turns space into a kind of cosmic glue. But one of the first things Thomson will do is turn the machine off for engineering work. It will not restart until his term is nearly over.<\/p>\n In an office on the first floor of the Cavendish laboratory, past a model of the DNA double helix discovered in Cambridge by James Watson and Francis Crick more than 70 years ago, Thomson is far from disconsolate about the shutdown. If anything, he is relishing what the next five years hold.<\/p>\n \u201cThe machine is running brilliantly and we\u2019re recording huge amounts of data,\u201d he says. \u201cThere\u2019s going to be plenty to analyse over the period. The physics results will keep on coming.\u201d<\/p>\n Thomson\u2019s background is far from academic: he went to comprehensive school in Worthing, West Sussex, and got a taste for physics only after reading a popular book about science at Cern<\/a> in his early teens. \u201cIt kind of set my direction,\u201d he says. \u201cI wanted to understand how the universe worked.\u201d He became the first in his family to go to university, reading physics at Oxford.<\/p>\n The LHC accelerates protons, the nuclei of hydrogen atoms, to nearly light speed inside a 27km-long (16-mile) ring under the French-Swiss countryside. At four points around the ring, protons zipping in one direction are steered into others rushing towards them. The energy on impact creates a shower of new particles that are recorded by the LHC\u2019s detectors. In line with Einstein\u2019s seminal equation E=mc2, more energy yields more massive particles.<\/p>\n The Large Hadron Collider (LHC) nuclear particle accelerator at Cern, pictured in 2018. Photograph: EThamPhoto\/Getty Images<\/p>\n Starting in June, the shutdown will make way for the high-luminosity LHC<\/a>, a major upgrade that involves installing powerful new superconducting magnets to squeeze the collider\u2019s proton beams and make them brighter. This will raise the number of collisions in the machine tenfold. The detectors are being strengthened too, making them better able to capture the subtle signs of new physics collisions can reveal. \u201cIt\u2019s an incredibly exciting project,\u201d Thomson says. \u201cIt\u2019s more interesting than just sitting here with the machine hammering away.\u201d<\/p>\n If the upgrade works, the LHC will make more precise measurements of particles and their interactions, which could find cracks in today\u2019s theories that become the foundations for tomorrow\u2019s. One remaining mystery surrounds the Higgs boson. Elementary particles gain their masses from the Higgs, but why the masses vary as they do is anyone\u2019s guess. It is not even clear how Higgs bosons interact with one another. \u201cWe could see something completely unexpected,\u201d Thomson says.<\/p>\n Getting the high-luminosity LHC up and running will dominate Thomson\u2019s five-year tenure. But a much larger, and more controversial, project requires his attention, too. The LHC reaches the end of its life around 2041 and Cern\u2019s member states must decide what comes next. The frontrunner is a colossal machine called the Future Circular Collider<\/a> or FCC.<\/p>\n map<\/a><\/p>\n