As 2012 draws to a close, physicists are celebrating — and being celebrated for — the end of a four-decade scientific quest to find a subatomic particle known as the Higgs boson. The discovery, made at the $10 billion Large Hadron Collider and reported in July, won honors this week as Science magazine's Breakthrough of the Year as well as a piece of the spotlight in Time magazine's Person of the Year package.
But the story of what some have nicknamed "the God particle" isn't over yet. (Physicists hate that nickname, by the way.)
"This particle has the potential to be a portal to a new landscape of physical phenomena that is still hidden from us," the scientific team behind the LHC's Compact Muon Solenoid detector writes in a Science paper that lays out the details behind the discovery.
That sentiment comes through as well in another paper from the LHC's ATLAS collaboration, which found results consistent with those from the CMS detector. The ATLAS scientists say finding the particle appears to provide the "last missing piece" in the Standard Model, the scientific theory that explains the subatomic realm — but also sets the stage for further studies "to explore the physics that must lie beyond" the Standard Model.
Both teams said they detected a particle that matched the quarry they sought, with a mass in the range of 125 billion electron volts. But they haven't yet quite confirmed that its characteristics fully conform with the theoretical particle that was proposed in the 1960s to fill in the Standard Model's remaining gaps.
That particle would help explain why some fundamental particles, such as the W and Z bosons, possess mass — while others, such as photons, don't. Physicists can see that such a mechanism must exist; otherwise, the cosmos just wouldn't work. The problem is figuring out how the mechanism is structured. The Higgs boson, and its associated Higgs field, fills the bill.
There's still some question whether the new particle reported this year is the Higgs boson, as described in the traditional Standard Model, or part of a more complex Higgs mechanism that may include other particles. Last week, there was a brief kerfuffle over whether the data from ATLAS hinted at two Higgs particles — but as of now, the leading view is that those hints are just statistical fluctuations that will eventually disappear. The definitive word is expected to come at a conference in March.
By that time, the LHC will be shut down for a major upgrade. The particle collider, housed in a 17-mile-round (27-kilometer-round) underground tunnel beneath the French-Swiss border near Geneva, has been running at energies of up to 8 trillion electron volts — but the upgrade will allow it to operate at 13 to 14 TeV starting in 2015. That's when the really way-out discoveries, relating to mysteries such as supersymmetry or the nature of dark matter, could come to light.
Why should we care about the Higgs boson? It may not bring us a better iPhone next year — but a better understanding of fundamental physics typically leads to better applications down the line. Just ask the inventors of medical scanners, microwave ovens or laser devices. For more on the practical implications of research at the LHC, check out our interactive interview with physicist Michio Kaku.
The same disclaimer goes for Science's runner-up breakthroughs of the year. You may not see how some of these discoveries can relate to everyday life — but someday, you or your children will:
Unraveling the Denisovan genome: In late 2010, anthropologists used genetic tools to discover a new type of human ancestor that lived in Siberia tens of thousands of years ago, dubbed the Denisovans. This year, they used a new technique to compare the Denisovan genome with those of modern-day populations — and confirmed that some parts of the Denisovan genetic heritage were passed on. That's right, kids: Our ancestors did it with Denisovans. The new technique is expected to yield a high-quality version of the Neanderthal genome in 2013.
Making eggs from stem cells: Japanese researchers coaxed mouse stem cells into becoming viable eggs that produce healthy offspring. There are a few caveats: The eggs still have to be hosted by an actual mouse during one stage of their maturation, and the technique doesn't yet work with human cells. But the project represents another significant step in the fight against infertility.
Curiosity's landing system: Perhaps the most amazing thing about the Curiosity rover's landing on Mars in August was that a system designed to lower the rover from a rocket-powered, hovering platform actually worked. NASA engineers acknowledged that the idea seemed crazy but insisted it was the "least crazy" way to get the 1-ton payload safely to the surface. The "sky crane" concept worked so well that NASA plans to do it again in 2020. For more about the Curiosity mission, check out our "Year in Space" roundup.
X-ray laser reveals protein structure: Scientists used intense, ultra-short X-ray pulses from a free-electron laser to collect data on the 3-D structure of proteins — and single-shot images of an intact virus. "The grand goal is to push X-ray diffraction to its ultimate limit and use an X-ray laser to decipher a protein structure by zapping individual molecules," Science's editors write.
Precision engineering of genomes: If you haven't heard about TALENs and CRISPR yet, you will — at least if genetic engineering is your thing. These are new tools for "editing" the genomes of creatures ranging from zebrafish to rats and crickets. Even human cells are being tweaked for research purposes. "Some researchers now think TALENs [transcription activator-like effector nucleases] will become standard procedure for all molecular biology labs," the editors say.
Majorana fermions detected, sort of: Seventy-five years ago, Italian physicist Ettore Majorana theorized that a weird type of subatomic particle existed that could act as its own antiparticle. This year, Dutch physicists reported tentative signs that the particles have at last been detected. If their existence is confirmed, Majorana fermions would have properties that make them perfectly suited for quantum computing.
ENCODE zooms in on human genome: After a decade of research, a $288 million project to trace all the threads that make up the human genome issued a blizzard of scientific papers. The studies suggested that only a small percentage of our DNA is wrapped up in our genes. At the time, much was made of the fact that what was once called "junk DNA" plays an important role in our genetic makeup. But we knew that already, right? The important thing is that Project ENCODE ("Encyclopedia of DNA Elements") has made a grand start toward reading, and understanding, our book of life.
Better brain-machine interfaces: Is the "Star Trek" nightmare vision of the Borg coming to pass? Not yet: We are not being assimilated into machinery. But in the future, it should become easier for us to assimilate machinery when the need arises. Researchers are perfecting techniques for controlling artificial limbs, computers or other devices with our thoughts alone. Someday even physicist Stephen Hawking might benefit from mind-reading systems.
A new door in neutrino physics: Researchers caught a rare type of exotic particle known as an electron antineutrino in the act of disappearing, at an experimental facility in China — and that vanishing trick provided yet another long-sought puzzle piece in subatomic physics. The researchers said they measured the last parameter describing how different types of neutrinos morph into each other. For what it's worth, that parameter, the mixing angle known as theta13, equals 8.8 degrees, plus or minus 0.8 degrees. The fact that the value isn't zero could help explain why there's so much matter and so little antimatter in our universe.
Frontiers for 2013: In addition to 2012's breakthroughs, Science's editors highlighted six scientific areas to watch in 2013: single-cell DNA sequencing, the Planck probe's study of the cosmic microwave background, the Human Connectome Project, ultra-deep ice drilling at Antarctica's Lake Vostok, cancer immunotherapy research and basic plant research.
More about the Higgs quest:
- How will Nobel Prizes handle Higgs hassle?
- Comics go beyond the Higgs boson
- Gallery: Your guide to the particle zoo
- Cosmic Log archive on Higgs boson
- Special report on the Big Bang Machine
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.