‘Physics is like sex. Sure, it may give some practical results, but that's not why we do it,' said theoretical physicist Richard Feynman. I saw what he meant when I visited an exhibition of the Large Hadron Collider (LHC) where the God
Particle was discovered. Scientists were clearly having loads of fun, but practical results were scarce. How come?
Why is the biggest breakthrough in Particle Physics still a mystery?
These brilliant scientists found the God Particle - the Higgs Boson - using the LHC located 100m underground near Geneva, yet they did a pretty poor job explaining the significance of their discovery.
So I wondered: If the Conseil Européen pour la Recherche Nucléaire (CERN) couldn’t articulate this momentous breakthrough, how did they persuade so many governments to shell out the 10 billion Euros needed to build the Huge Hadron Collider?
According to ExtremeTech, the Higgs Boson is the most expensive particle of all time, and its discovery had been at the top of CERN’s agenda for decades,
All show and no tell
The exhibition was at Sydney's Powerhouse Museum a while ago, on loan from the Science Museum in London.
The website said that the exhibition ‘blends theatre, video and sound art with real artefacts from CERN, recreating a visit to the famous particle physics laboratory. Go behind the scenes to witness the uncovering of the Higgs boson, explore the 27-km collider and its cathedral-sized detector caverns, and discover how studying the subatomic world can point the way to a fuller understanding of our universe … See history being made. Meet engineers who build the impossible. Walk the tunnels of CERN. Stand in the heart of a collision. Witness a moment of discovery. Step inside the world’s greatest experiment.’
The prospect was enthralling, especially for a technology marketer like me.
How about some context?
The exhibition does some things reasonably well, but there is some very odd sequencing - like putting the particle physics timeline at the exit instead of the entrance.
After entering the exhibition space, visitors meander through cases of arcane 19th century instruments with no idea why they're there or where they fit, before entering the main exhibition where the digital theatre plays out .
It's only at the end - an hour later, right at the exit - that the timeline and the reason for showing all those obscure artifacts is revealed. Very odd.
There is also a video, a dramatisation of the control room of the LHC, showing researchers talking about how they found the Higgs Boson. That was just a little over my head.
With the help of various narrators, the theatre reveals the dramatic ‘unblinding’ (the discovery of the particle), the 60-year hunt for the particle that Professor Higgs from Edinburg had predicted the existence of, the fierce competition between 2 scientific teams to discover it.
Then a young female scientist presents the breakthrough to an astonished world, and talks about the sleepless nights before that big moment.
The excitement and anticipation were thrilling, and then: nothing. I looked at my companion who also looked perplexed. Had we missed something?
A little later, we fell upon a reconstruction of this sleepless researcher's office, and here at last I saw the 'unblinding': a small blip on a graph.
We looked at each other again and shook our heads.
The Large Hadron Collider – why bother?
Every good story has a beginning and an end, but they were both missing here.
The exhibition dived straight into particle physics and the search for the Higgs Boson, the missing piece. It was loaded with pictures of the LHC, and its astonishing technology, the immense electronics and huge electric currents needed to accelerate particles to near light speed, and then bend them and steer them toward high-speed, high-energy collisions.
When the research project was announced, Stephen Hawking said it would allow scientists to recreate conditions similar to those after the Big Bang, and said it was vital for it to go ahead ‘if the human race is not to stultify and eventually die out.’
The Large Hadron Collider was designed to smash together trillions of subatomic particles, and supercomputers were used to sift through vast amounts of data looking for the few collisions that showed evidence of the Higgs Boson.
By smashing together known particles such as protons at near light speed, scientists also hope to discover new subatomic particles (hadrons).
Ah, is that where the name comes from? At last we were closer to understanding the purpose of this huge project: it’s not to address urgent problems mankind needs to solve for its survival, but for theoretical physics to learn more about the origin and make-up of the universe.
The LHC was built to help scientists:
- Better understand how the universe grew out of the Big Bang
- Learn what the universe is made of, how it behaves, and how to predict its future
- Learn more about black holes by using the LHC for simulation
- Discover (suspected) as yet undiscovered particles including the Higgs boson
- Reveal extra dimensions of space, beyond the three we currently see.
So that’s why 10,000 scientists built a 27 km underground tunnel with huge detectors, connected up thousands of kilometres of wire and hundreds of computers on different sides of the ring to capture the collisions.
The CMS (Compact Muon Solenoid) detector is the biggest at 22 metres long, 15 metres in diameter, and 14,000 tonnes. The CMS team that built and now operates
the detector is the biggest, with 3,800 people representing 200 scientific institutes and 43 countries.These figures read like the dimensions in a
Matthew Reilly novel.
The possible existence of another dimension has long intrigued scientists.
‘Einstein’s general theory of relativity tells us that space can expand, contract, and bend,’ CERN tells us. ‘Now if one dimension were to contract to a size smaller than an atom, it would be hidden from our view. But if we could look on a small enough scale, that hidden dimension might become visible again.’
Image source: UK SUN, in an article that says: ‘photos taken above CERN’s Large Hadron Collider lead to wild new conspiracy theories and “prove portals are opening”.’
The same CERN article says that the discovery of a Z- or W-like particle (the Z and W bosons are carriers of the electroweak force) with a mass 100 times larger for instance, ‘might suggest the presence of extra dimensions. Such heavy particles can only be revealed at the high energies reached by the Large Hadron Collider.’
Professor Steve Giddings speaks of a ‘supersymmetry’, a mirror universe where all known particles have partner particles with related properties that could be discovered by the LHC. He says these superpartners may also make up dark matter, and that could lead to two great discoveries being made at once. He adds, ‘If the Higgs has been detected, a completely new kind of matter has been discovered.’ More here & here.
After the Higgs Boson was discovered in 2013, the LHC received a massive upgrade that took 2 years. It went back into operation in 2016 with its energy levels almost doubled, which is expected to expand the potential for more ground-breaking discoveries.
At full throttle, the scientists expect to shoot two beams each containing around 273,600 billion protons through the collider in opposite directions, causing a billion collisions a second at near light speeds, with a joint energy level of 13 TeV. A TeraelectronVolt is about the level of energy generated by a flying mosquito, but bear in mind that a mosquito is the size of a car compared to a proton. In other words, 13 TeV is a huge amount of kinetic energy for a subatomic particle.
Observationdeck tells us that CERN put out a 5 minute video explaining the upgrade they just completed, and were planning high-luminosity upgrades that ‘will transform the LHC into a facility for precision studies’ over the next decade.
The huge detectors also received massive upgrades. Late in 2015, when another small bump was found on a graph of analysed data, Gavin Hesketh at the New Scientist wrote that researchers thought it might have been ‘the first sign of a particle 800 times heavier than a proton that could fit the predictions of supersymmetry. A flood of more than 500 theory papers followed in an attempt to explain it, but after adding the data taken at the LHC so far in 2016, the bump went away. The 2015 signal was just noise after all.’
Image source: Maximilien Brice/CERN
Theoretical physics at this level is a long term adventure, but we still didn't know why the LHC had to be built 100m underground and kept running at minus
271 degrees Celsius. Digging deeper after our visit, we found another missing puzzle piece: CERN tells us that the electric currents in the LHC run up to 12,000 Amperes. That makes superconductors essential, and they work best at close to absolute zero.
Wouldn't this have been nice to know earlier in our journey?
Any practical benefits?
Malina Kirn, a graduate student in CMS Technology development, answered this question in a Quora discussion by suggesting applications in cancer therapy, manufacturing, medical and industrial imaging, pattern recognition and grid computing.
None of these sound like significant breakthroughs, and some of the core technology benefits she mentions are much more likely to offer payback.
One example Kirn gives is that of quantum mechanics, which is over a hundred years old and in its early days generated ‘interesting scientific puzzles which had no known practical application.’
Now we know that quantum mechanics led to the invention of transistors and semiconductors, which have profoundly changed our world. Now that's impressive.
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