- Aug 12, 2018
Pope Francis pleaded the scientific community to halt operations on the Large Hadron Collider (LHC) in an official Vatican release as scientists at the Large Hadron Collider next week are hoping to experiment with a possible connection with a parallel universe outside of our own.
The Pope’s criticism comes days after scientists at the CERN centre in Geneva, Switzerland, revealed this week plans to fire up the LHC ‘atom smasher’ to its highest energy levels ever in a bid to detect – or even create – miniature black holes and possibly “create an opening in the space-time fabric”.
Another skeptic of the project is none other than respected physicist Stephen Hawking who has recently warned the end of the world could be sparked by the elusive ‘God particle’.
Pope Francis warned the scientific community of “testing God’s limits” after the announcement of the reopening of the LHC, which has been undergoing massive repairs and been shut down for the past two years
The Pope appeared visibly distraught as he addressed the crowd of tens of thousands of followers present at St-Peter’s square for the occasion for one of his longest speeches to date.
“My fellow Christians, we are living in desperate times,” he told the crowd.
“Science is about to test the limits of God and his creation. God has created boundaries between the world of the living and the world of the dead. Are these scientists about to unleash upon us the Gates of Hell?” he asked his followers, visibly shaken.
Last October, over 400 top physicists signed a petition warning that the Higgs potential might become unstable at energies above 100bn giga-electron-volts (GeV) and asking governments to keep experiments under these levels.
This is how CERN’s Large Hadron Collider looks during the 2019 shutdown
29 Apr 2019 Matin Durrani
Into the future: the Large Hadron Collider is currently shut down in the first phase of an upgrade to the High-Luminosity LHC. (Courtesy: Matin Durrani)
When Physics World was invited by the UK’s Science and Technology Facilities Council (STFC) to visit CERN and meet a bunch of physicists working on the world’s biggest physics experiment, it’s hard to think of a good reason to say “no”.
And so last week I flew to Geneva to join a group of other UK science journalists on a two-day tour of CERN, having a nosey round the LHC and two of its experiments – LHCb and the Compact Muon Solenoid (CMS) – and learning about CERN’s plans for the future.
Descending 100 m underground in an industrial lift, first stop was the LHC itself, which is normally out of bounds but is currently in the midst of a two-year shutdown as CERN begins work on an upgrade to the LHC called the High-Luminosity LHC (HL-LHC).
What a job!: Paul Collier is the marvellously titled head of beams at CERN. (Courtesy: Matin Durrani)
There to greet us was Paul Collier, CERN’s marvellously titled “head of beams” (who I have just realized is one “D” short of the best-ever example of nominative determinism – Collier/Collider). He explained how the LHC is tilted at angle of 1.4° to the horizontal to keep the accelerator level with respect to the surface overground.
Collier was there on the fateful day in 2008 when, just after the LHC fired up, two superconducting contacts in one of the LHC’s magnets separated, creating an arc of current that damaged the machine and led to a massive repair programme that took almost a year to complete.
Of course, the LHC isn’t there just to accelerate protons, the idea is to collide them too. And so it was back overground to the control room of the LHCb experiment, where it was reassuring to see an emergency panel with a big, red “stop” button.
Don’t stop me now: the control panel inside the LHCb control room. (Courtesy: Matin Durrani)
Much of the focus at CERN has been the two “general-purpose” experiments — ATLAS and the Compact Muon Solenoid (CMS), which together found the Higgs boson in 2012. But one could argue that there’s been more interesting work from the LHCb, which has only this year reported further evidence for pentaquarks and for symmetry violation in charm mesons for the first time – a finding that could help explain why there’s so much more matter than antimatter in the universe. Giving us the lowdown on the LHCb was Silvia Gambetta (University of Edinburgh), Mark Williams and Chris Parkes (both University of Manchester).
The people who antimatter: Silvia Gambetta (left), Mark Williams (centre) and Chris Parkes from the LHCb experiment. (Courtesy: Matin Durrani)Time for reflection: LHCb cavern at CERN during the 2019 shutdown. (Courtesy: Matin Durrani)
As I stared at the wiring on the LHCb, it’s mind-boggling how any of it actually works. One stray cable and surely the whole thing will conk out?
Wired up: the LHCb detector close-up reveals how this really is just a giant physics experiment. (Courtesy: Matin Durrani)
Most of the current shutdown is focused on preparatory civil-engineering works for the HL-LHC, but CERN staff are using the two-year break to carry out vital maintenance on the accelerator and experiments before the LHC switches back in 2021 for a final three-year run. After all, when the LHC’s in use, it’s on for two or three years at a time – and you can’t nip down and carry out running repairs. Or as physicist Dave Barney from CMS put it: “It’s like having an experiment on the Moon – you can’t modify it when you want.”
Practical focus: Dave Barney is building a “high-granularity” calorimeter for the endcaps of the CMS detector. (Courtesy: Matin Durrani)
Barney is responsible for validating prototype modules for a new calorimeter for the “end-caps” on the CMS experiment. The current calorimeter has several parts, including one that contains 80,000 lead-tungstate crystals, which are super-dense and therefore great at measuring the energy of particles that fly off from collisions. Trouble is, they go dark and won’t stand the rigours of the HL-LHC.
This is especially true of the endcaps, where the 14,000 crystals will have to be replaced with something else. Barney and colleagues are therefore developing a new “high-granularity” calorimeter that will include about 30,000 honeycomb-shaped silicon modules, each divided into about 200 smaller hexagons – a total of about six million detectors!
This is the future: 30,000 of these detector elements, which consist of copper/tungsten, silicon and circuit-board layers, will be needed for the CMS experiment as part of the High-Luminosity LHC. (Courtesy: Matin Durrani)
Barney was talking to us about the end-caps as if they’re part of just another physics experiment. Which I suppose they are – that is, until you go 100 m back underground to see CMS and you realize just how big it is and why “compact” is the strangest choice of word for the CMS. The end-caps are the big lumpy object to the right of the scaffolding.
Sunken treasure: the CMS experiment during the 2019 shutdown. (Courtesy: Matin Durrani)Heart of the matter: the “end-cap” on the CMS experiment. (Courtesy: Matin Durrani)
For all the talk of HL-LHC, or “High-Lumi” as I often heard it called for short, there are already plans for the next collider after the LHC. Depending on who you talk to, CERN will, over the next 12 months, fall in line either behind the Compact Linear Collider (CLIC) or the 100 km Future Circular Collider (FCC).
The FCC, if built, would be about as long as the giant £15bn Crossrail railway tunnel across central London. Except that it would contain an accelerator with thousands of magnets, using technology that’s been pushed to the limits, searching for physics we don’t yet know anything about, and involving thousands of scientists and engineers from across the globe – many of whom have perhaps not yet even been born. If it happens, the FCC will, like CERN itself, be an incredible human feat.
• You can find out more from my visit by listening to this Physics World Weekly podcast, which features Rhodri Jones (head of beam instrumentation), Chris Parkes (LHCb), Ben Krikler (CMS) and Sarah Williams(ATLAS).