The Large Hadron Collider: We’ve Definitely Found the Higgs Boson

higgs-boson1In July 2012, the CERN laboratory in Geneva, Switzerland made history when it discovered an elementary particle that behaved in a way that was consistent with the proposed Higgs boson – otherwise known as the “God Particle”. Now, some two years later, the people working the Large Hadron Collider have confirmed that what they observed was definitely the Higgs boson, the one predicted by the Standard Model of particle physics.

In the new study, published in Nature Physics, the CERN researchers indicated that the particle observed in 2012 researchers indeed decays into fermions – as predicted by the standard model of particle physics. It sits in the mass-energy region of 125 GeV, has no spin, and it can decay into a variety of lighter particles. This means that we can say with some certainty that the Higgs boson is the particle that gives other particles their mass – which is also predicted by the standard model.

CERN_higgsThis model, which is explained through quantum field theory  – itself an amalgam of quantum mechanics and Einstein’s special theory of relativity – claims that deep mathematical symmetries rule the interactions among all elementary particles. Until now, the decay modes discovered at CERN have been of a Higgs particle giving rise to two high-energy photons, or a Higgs going into two Z bosons or two W bosons.

But with the discovery of fermions, the researchers are now sure they have found the last holdout to the full and complete confirmation that the Standard Model is the correct one. As Marcus Klute of the CMS Collaboration said in a statement:

Our findings confirm the presence of the Standard Model Boson. Establishing a property of the Standard Model is big news itself.

CERN_LHCIt is certainly is big news for scientists, who can say with absolute certainty that our current conception for how particles interact and behave is not theoretical. But on the flip side, it also means we’re no closer to pushing beyond the Standard Model and into the realm of the unknown. One of the big shortfalls of the Standard Model is that it doesn’t account for gravity, dark energy and dark matter, and some other quirks that are essential to our understanding of the universe.

At present, one of the most popular theories for how these forces interact with the known aspects of our universe – i.e. electromagnetism, strong and nuclear forces – is supersymmetry.  This theory postulates that every Standard Model particle also has a superpartner that is incredibly heavy – thus accounting for the 23% of the universe that is apparently made up of dark matter. It is hoped that when the LHC turns back on in 2015 (pending upgrades) it will be able to discover these partners.

CERN_upgradeIf that doesn’t work, supersymmetry will probably have to wait for LHC’s planned successor. Known as the “Very Large Hadron Collider” (VHLC), this particle accelerator will measure some 96 km (60 mile) in length – four times as long as its predecessor. And with its proposed ability to smash protons together with a collision energy of 100 teraelectronvolts – 14 times the LHC’s current energy – it will hopefully have the power needed to answer the questions the discovery of the Higgs Boson has raised.

These will hopefully include whether or not supersymmetry holds up and how gravity interacts with the three other fundamental forces of the universe – a discovery which will finally resolve the seemingly irreconcilable theories of general relativity and quantum mechanics. At which point (and speaking entirely in metaphors) we will have gone from discovering the “God Particle” to potentially understanding the mind of God Himself.

I don’t think I’ve being melodramatic!

Source: extremetech.com, blogs.discovermagazine.com

Work Begins on Successor to Large Hadron Collider

CERN_upgradeIn 2012, scientists working for the CERN laboratory in Switzerland announced the discovery of the Higgs Boson. After confirming this momentous discovery, CERN scientists indicated in April of 2013 that the Large Hadron Collider was being taken offline in order to upgrade its instruments for the next great project in its ongoing goal of studying the universe. And this past February, work began in earnest on planning for the LHC’s successor.

This massive new marvel of scientific instrumentation, which has been dubbed the “Very Large Hadron Collider”, will measure some 96 km (60 mile) in length – four times as long as its predecessor – and smash protons together with a collision energy of 100 teraelectronvolts (which is 14 times the LHC’s current energy). All of this will be dedicated to answering the questions that the first-time detection of the Higgs Boson raised.

Peter Higgs (who proposed the Higgs boson), hanging out at LHC’s CMS detector
Peter Higgs (who proposed the Higgs boson), hanging out at LHC’s CMS detector

While this discovery was a watershed moment, its existence poses more questions than it answers; and those answers probably can’t be answered by the LHC. Thus, to keep high-energy physics moving forward, the international team of scientists at CERN knew they needed something more accurate and powerful. And while the LHC is slated to remain in operation until 2035, it is the VLHC that will addressing the question of how the Higgs get’s its mass.

Basically, while the discovery of the Higgs Boson did prove that the Standard Model of particle physics is correct, it raised some interesting possibilities. For one, it suggests that particles do indeed gain their mass by interacting with a pervasive, ubiquitous Higgs field. Another possibility is that the Higgs boson gains its heaviness through supersymmetry — a theory that proposes that there’s a second, “superpartner” particle coupled to each and every Higgs boson.

CERN_LHCScientists have not yet observed any of these superpartners, and to discover them, a stronger collider will be necessary. It is hoped that, when the LHC powers up to 14 TeV by the end of 2014, its scientists will discover some signs of supersymmetry. This will, in turn, inform the creation of the LHC’s successor, which still remains a work in progress. And at this point, there are two groups presenting options for what the future of the VLHC will be.

One group consists of Michael Peskin and a research group from the SLAC accelerator in California, who presented an early VLHC concept to the US government back in November. This past February, CERN itself convened the Future Circular Collider study at the University of Geneva. In both cases, the plan calls for a 80-100km (50-62mi) circular accelerator with a collision energy of around 100 TeV.

large_hadron_colliderAs the name “Very Large Hadron Collider” implies, the plans are essentially talking about the same basic build and functionality as the LHC — just with longer tunnels and stronger magnets. The expected cost for either collider is around $10 billion. No telling which candidate will be built, but CERN has said that if it builds the successor, excavation will probably begin in the 2020s, so that it’s completed before the LHC is retired in 2035.

In the shorter term, the International Linear Collider, a 31-kilometer-long (19.2 mile) particle accelerator, is already set for construction and is expected to be completed in or around 2026. The purpose of this device will be to conduct further tests involving the Higgs Boson, as well as to smash electrons together instead of protons in order to investigate the existence of dark energy and multiple dimensions.

center_universe2The future of high-energy physics is bright indeed, and with all this research into the deeper mysteries of the universe, we can expect it to become a much more interesting place, rather than less of one. After all, investigating theories does not dispel the mystery of it all, it only lets you know where and how they fell short. And in most cases, it only confirms that this thing we know of as reality is beyond what we previously imagined.

Sources: extremetech.com, indico.cern.ch