2016 held some wonderful physics instants—hello gravitational waves! Like shining a laser beam through antimatter, other moments were experimentally striking, but don’t have exactly the same oomph as colliding black holes. And some were just not completely inflate: Dark matter still won’t reveal itself. However, every experimental let down opens up new avenues for inquiry. The things physicists did, and didn’t, discover in 2016 are hints about what to anticipate in the science in the coming years.
Hopes for a New Particle, Destroyed
In late December 2015 CERN, the European center for high energy physics research, released data showing that there may be a fresh particle afoot. A kind of neutrino? Though scientists said it was perhaps (even probably) a statistical fluke, delight spread like a shockwave. In just a month, scientists had posted 500 theoretical articles related to the particle on the preprint arXiv server.
But dreams of post-Standard Model physics were dashed as days lengthened into summer. Nope. And, as the Large Hadron Collider went to bed this month for the remaining year, the machine had failed to show the strategy to a brand-new particle.
Yay, We Found Gravitational Waves!
A century after Albert Einstein’s forecast, physicists supported the presence of gravitational waves by detecting ripples in spacetime created when two black holes crashed together 1.4 billion years ago. He believed such signals would not be so strong humans would never have the ability to find them. Scientists at the Laser Interferometer Gravitational-Wave Observatory were pleased to prove him both right and wrong.
Team LIGO has spent much of 2016 updating its observatories in Washington and Louisiana after declaring their discover in February. And in late November, LIGO began listening again, straining to hear new ripples. Together with the recent launching of their citizen science program “Gravity Spy,” you can help them tune in.
LUX wrapped up its observations in May. But in July, it declared that it had not found any telltale signals of WIMPs. And while, yes, this is a little bit of a bummer, physicists aren’t giving up on the investigation. The LUX-ZEPLIN experiment will replace LUX in the Sanford Underground Research Facility. It should have 70 times the sensitivity of LUX and is anticipated to be running in 2020 and up.
This summer the BOSS program released its map—the greatest ever, containing more than a million galaxies, allowing physicists to make the most effective estimates yet of the poorly comprehended “dark energy” that’s accelerating the expansion of the universe. What exactly does a map of a million galaxies look like? Kind of like Jackson Pollock wed a pointillist.
Identical Twin Particles end up being Exceptional
Matter and antimatter are clearly different— the universe is dominated by matter, while scientists can only just catch snippets of antimatter. But why this is so is a puzzle. The Standard Model says the two should be basically the same, so any indicators that they can break so-called charge-parity symmetry can offer clues to why the universe favored matter over antimatter.
In summer, the T2K Cooperation, located in Japan, presented one such clue. They trained a neutrino beam in the Super Kamiokande underground detector in Kamioka — and when they measured them, they saw more electron neutrinos and fewer electron antineutrinos than would be expected. What this means is unclear, but the path could light toward understanding the difference between antimatter and matter.
Color for the First Time of Antimatter Seen
Late-breaking news rounded out the year in physics. The ALPHA collaboration saw, for the very first time, the colour of antimatter.
Simply managing to make this kind of comparison is an accomplishment of engineering that is experimental.