gravitational waves tagged posts

A new theory may have far reaching implications for the multiverse paradigm. Credit: X-ray: NASA/CXC/PSU/L. Townsley et al; Optical: UKIRT; Infrared: NASA/JPL-Caltech

Professor Stephen Hawking’s final theory on the origin of the universe, which he worked on in collaboration with Professor Thomas Hertog from KU Leuven, has been published in the Journal of High Energy Physics. The theory, which was submitted for publication before Hawking’s death earlier this year, is based on string theory and predicts the universe is finite and far simpler than many current theories about the big bang say...

Drs Eric Thrane and Rory Smith. Credit: Image courtesy of Monash University

Deep space is not as silent as we have been led to believe. Every few minutes a pair of black holes smash into each other. These cataclysms release ripples in the fabric of spacetime known as gravitational waves. Now Monash University scientists have developed a way to listen in on these events. The gravitational waves from black hole mergers imprint a distinctive whooping sound in the data collected by gravitational-wave detectors. The new technique is expected to reveal the presence of thousands of previously hidden black holes by teasing out their faint whoops from a sea of static.

Last year, in one of the biggest astronomical discoveries of the 21st century, LIGO Scientific Collaboration (LSC) and Virgo Collabo...

Sagittarius A*, the black hole at the centre of our own galaxy. Credit: NASA/CXC/MIT/F. Baganoff et al.

Gravitational waves may be forged in the heart of the galaxy, says a new study led by PhD student Joseph Fernandez at Liverpool John Moores University. He sets out the work in a presentation on 3rd April at the European Week of Astronomy and Space Science in Liverpool. Gravitational waves (GWs) are small ripples in space-time that spread throughout the universe.

When there is a change in air pressure on Earth, this change moves outwards in the form of sound waves. Analogously, when pairs of compact objects – like black holes (BHs) or neutron stars (NSs) – form binaries and rotate around one another, the gravitational field around them changes, producing GWs that also move outwards.

This ...

This graphic shows the X-ray counterpart to the gravitational wave source GW170817, produced by the merger of two neutron stars. The left image is the sum of observations with NASA’s Chandra X-ray Observatory taken in late August and early Sept. 2017, and the right image is the sum of Chandra observations taken in early Dec. 2017. The X-ray counterpart to GW170817 is shown to the upper left of its host galaxy, NGC 4993, located about 130 million light years from Earth. The counterpart has become about four times brighter over three months. GW170817 was first observed on Aug. 17, 2017. Credit: NASA/CXC/McGill/J.Ruan et al.

The afterglow from the distant neutron-star merger detected last August by LIGO has continued to brighten – much to the surprise of astrophysicists studying the aftermath...