Explainer: Just what are Einstein's gravitational waves?

WASHINGTON -- Astronomers on Thursday announced that their new billion-dollar U.S. observatory has detected a gravitational wave, a phenomenon Albert Einstein predicted a century ago in his theory of general relativity.

See Full Article

Here's what that breakthrough means.

WHAT IS A GRAVITATIONAL WAVE?

Gravitational waves are extremely faint ripples in the fabric of space and time that come from some of the most violent events in the universe. In this case, it is from the merger of two black holes 1.3 billion light-years away. The way to think of this is to imagine a mesh net and visualize pulling on its ends. Those kinks are sort of like what a gravitational wave does.

WHAT IS SPACE-TIME?

Space-time is the mind-bending, four-dimensional way astronomers see the universe. It melds the one-way march of time with the more familiar three dimensions of space.

General relativity says that gravity is caused by heavy objects bending space-time. And when massive but compact objects like black holes or neutron stars collide, their immense gravity causes space-time to stretch or compress.

HOW IS THIS "HEARING" THE COSMOS?

Scientists mostly use the word "hear" when describing gravitational waves, and the data does, in fact, arrive in audio form. The researchers can don headphones and listen to the detectors' output if they want. On Thursday, to prove they found a gravitational wave, the researchers played a recording of what they called a chirp.

HOW CAN THEY BE CERTAIN THIS IS REAL?

Astronomers sat on the discovery for nearly five months, since Sept. 14, checking back and forth to make sure it was right. They considered all sorts of Earth-bound interference or noise, examined the possibilities and eventually dismissed them.

The astronomers are so cautious that they routinely have other scientists deliberately inject false data to test their abilities. In those tests, the observatory team was able to show that the injected data wasn't real. In the case of the discovery announced Thursday, they are extra certain they are not seeing injected or hacked data because the system that allows false information to be inserted was down at the time.

In addition, the team of 1,004 scientists on the project looked over the data, and the results were then peer-reviewed by even more experts and published in the journal Physical Review Letters.

WHAT'S NEXT?

Expect more waves. It could be as many as a few a month or as little as a few per year. The observatory is also being further upgraded to hear even fainter, more distant waves.



Advertisements

Latest Tech & Science News

  • Ship lost in storm 136 years ago found in Georgian Bay

    Tech & Science CTV News
    Divers have discovered the site of a sunken ship near Colpoy’s Bay, Ont., an inlet off Georgian Bay, at least 136 years after the steamer sank during a winter storm. Great Lakes shipwreck diver and Minnesota resident Ken Merryman, along with his crew, set out to find the vessel, known as the Jane Miller, on a warm day in July. Source
  • Microsoft updates Bing search to highlight reputable results

    Tech & Science CTV News
    Harry Shum, executive vice president of Microsoft's Artificial Intelligence and Research, speaks at a Microsoft event in San Francisco, Wednesday, Dec. 13, 2017. (AP / Jeff Chiu) Source
  • Blue Origin launches, lands upgraded spacecraft with 'Mannequin Skywalker' aboard

    Tech & Science CBC News
    Private space company Blue Origin has successfully launched and landed an upgraded rocket and a new crew capsule that it bills as having "the largest windows in space." The seventh flight of the company's New Shepard suborbital spacecraft at the company's West Texas launch site Tuesday carried a test dummy called Mannequin Skywalker, equipped with sensors. Source
  • The world threw away nearly 45 million tons of technology last year

    Tech & Science CTV News
    BERLIN -- A new study claims 44.7 million metric tons (49.3 million tons) of TV sets, refrigerators, cellphones and other electrical good were discarded last year, with only a fifth recycled to recover the valuable raw materials inside. Source
  • Google opens AI centre in China as competition heats up

    Tech & Science CTV News
    Google announced Wednesday that it will open a new artificial intelligence research centre in Beijing, tapping China's talent pool in the promising technology despite the US search giant's exclusion from the country's internet. Artificial intelligence, especially machine learning, has been an area of intense focus for American tech stalwarts Google, Microsoft and Facebook, and their Chinese competitors Alibaba, Tencent and Baidu as they bid to master what many consider is the future of…
  • 'I Want a Hippopotamus For Christmas' wish granted, again

    Tech & Science CTV News
    Oklahoma City native Gayla Peevey has welcomed another hippopotamus to the city's zoo, more than 60 years after her song about wanting one for Christmas helped the facility purchase its first. The singer was on hand as the 26-year-old pygmy hippopotamus Francesca made her first Oklahoma public appearance since moving from the San Diego Zoo. Source
  • Scientists uncover fossils of 100-kilogram giant penguin

    Tech & Science CBC News
    Fossils from New Zealand have revealed a giant penguin that was as big as a grown man, roughly the size of the captain of the Pittsburgh Penguins. The creature was slightly shorter in length and about nine kilograms (20 pounds) heavier than the official stats for hockey star Sidney Crosby. Source
  • Global warming intensified Hurricane Harvey's rainfall, research shows

    Tech & Science CTV News
    NEW ORLEANS -- New studies find global warming's fingerprints were all over the record rainfall from Hurricane Harvey this year. While scientists say man-made climate change didn't trigger Harvey, two studies presented Wednesday calculate that a warmer, wetter world tripled the likelihood that the hurricane would douse and flood Houston. Source
  • Officials watching for oiled birds after sheen reported off Newfoundland

    Tech & Science CTV News
    FOGO ISLAND, N.L. - Federal officials say they are watching for oiled birds off the northern coast of Newfoundland and Labrador near Fogo Island after a report of a light oil sheen in the area. Source
  • What Canadians were curious about: Google searches suggest 2017 a tough year

    Tech & Science CTV News
    If you are what you Google, Canadians are a pretty broad-minded lot. Google has released its 17th annual survey of top-trending searches, and top-of-mind topics for Canucks in 2017 ranged from devastating hurricanes to deceased rock icons to the continuing political circus south of the border. Source