Caltech researchers detect first overtones of newly formed black hole

0 Comment(s)Print E-mail Xinhua, September 13, 2019
Adjust font size:

LOS ANGELES, Sept. 12 (Xinhua) -- Researchers at the California Institute of Technology (Caltech) have detected for the first time overtones of a newly formed black hole, according to a latest Caltech release.

When two black holes collide, they merge into one bigger black hole and ring like a struck bell, sending out ripples in space and time called gravitational waves.

Embedded in these gravitational waves are specific frequencies, or tones, which are akin to individual notes in a musical chord.

Caltech researchers detected two such tones for the first time in the "ringdown" of the newly formed black hole, according to the release.

Previously, it was assumed that only a single tone could be measured and that additional tones, called overtones, would be too faint to be detected with today's technologies, according to the study, published in the Sept. 12 issue of Physical Review Letters.

The results, which were based on reanalyzing data captured by the Laser Interferometer Gravitational-wave Observatory (LIGO), have put Albert Einstein's general theory of relativity to a new kind of test.

As merging black holes experience crushing gravity, studies of these events allow researchers to test the general theory of relativity under extreme conditions.

"This kind of test had been proposed long before the first detection, but everybody expected it would have to wait many years before detectors would be sensitive enough," said Saul Teukolsky, professor of Theoretical Astrophysics at Caltech.

"This result shows that we can start carrying out the test already with today's detectors by including the overtones, an unexpected and exciting result," he said.

LIGO made history in 2015 when it made the first-ever direct detection of gravitational waves, 100 years after Einstein first predicted them.

Since then, LIGO and its European-based partner observatory, Virgo, have detected nearly 30 gravitational-wave events.

Over the next few years, planned upgrades to LIGO and Virgo will make the observatories even more sensitive to gravitational waves, revealing more hidden tones, said the release. Enditem

Follow on Twitter and Facebook to join the conversation.
ChinaNews App Download
Print E-mail Bookmark and Share

Go to Forum >>0 Comment(s)

No comments.

Add your comments...

  • User Name Required
  • Your Comment
  • Enter the words you see:   
    Racist, abusive and off-topic comments may be removed by the moderator.
Send your storiesGet more from