A Decade of Discovery: Cardiff University Celebrates 10 Years Since the First Detection of Gravitational Waves

Scientists at Cardiff University are marking a significant milestone in their groundbreaking research on gravitational waves. Ten years have passed since the first-ever detection of these elusive signals, which revolutionized the field of astrophysics and expanded our understanding of the universe. The signal, detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015, revealed a pair of remote black holes merging and provided unparalleled information about their dramatic origins. Since then, LIGO has become a leading force in detecting gravitational waves, observing roughly one black hole merger every three days.

Key Takeaways:

• Researchers at Cardiff University played a pivotal role in laying the foundations for detecting gravitational waves, developing novel algorithms and software that are now standard search tools for detecting these elusive signals.
• The first detection of gravitational waves in 2015 was a result of Cardiff University's research on the development of signal models and data-analysis methods used to measure the properties of the signal, including the mass of black holes and the distance of the source.
• Ten years on, LIGO scientists have observed roughly one black hole merger every three days, with the network discovering over 300 black hole mergers to date.
• The recent breakthrough announced by LIGO scientists has tested an idea put forth by Stephen Hawking in 1971, verifying the black hole area theorem, which states that the total surface areas of black holes cannot decrease.
• The improvement in LIGO's sensitivity over the past decade has been significant, with the detection of signal GW250114 demonstrating a dramatic increase in clarity and precision.
• Analysis of the frequencies of gravitational waves emitted by the merger has provided the best observational evidence to date for the black hole area theorem.
• Cardiff University's involvement in the LIGO research has led to the development of novel algorithms and software that have improving the sensitivity of the LIGO detectors.
• Professors Mark Hannam and Stephen Fairhurst from Cardiff University have been at the forefront of this research, with Professor Hannam recalling the first detection and Professor Fairhurst serving as the spokesperson for the LIGO Scientific Collaboration (LSC).
• The LIGO detectors have achieved higher sensitivity than in previous runs, with the latest run, O4, discovering over 220 candidate black hole mergers, more than double the number caught in the first three runs.

Statistics:

• LIGO has detected a signal from the merging of two black holes carrying information about a pair of remote black holes that had spiralled together and merged after 1.3 billion years.
• The network of gravitational wave detectors, LVK (LIGO, Virgo, KAGRA), has captured a total of about 300 black hole mergers to date.
• During the current science run, O4, the LVK has discovered about 220 candidate black hole mergers, more than double the number caught in the first three runs.
• The LIGO detectors have achieved higher sensitivity than in previous runs, with the latest run, O4, detecting changes in space-time smaller than 1/10,000 the width of a proton.
• The black hole area theorem, put forth by Stephen Hawking in 1971, has been verified by the LIGO detection of gravitational waves, which have provided the best observational evidence to date for this theorem.

Sources:

• Cardiff University
• LIGO Scientific Collaboration (LSC)
• The Gravity Exploration Institute (GEI)
• The Laser Interferometer Gravitational-Wave Observatory (LIGO)