gravitational-waves

https://i.sstatic.net/TMUj3nKJ.png This is a fabricated period vs time plot of a gravitational wave for educational purpose. How can I determine the rate of change of frequency over time (df/dt) of the GW just from this graph?

https://i.sstatic.net/TMUj3nKJ.png This is a fabricated period vs time plot of a gravitational wave for educational purpose. How can I determine the rate of change of frequency over time (df/dt) of the GW just from this graph?

New gravitational wave observatories could detect ancient black hole mergers and reveal how the first stars shaped the early universe.

A few hundred million years after the Big Bang, the first stars ignited - literally the “let there be light” moment for the universe. Now known to astronomers as Population III, or Pop III, stars, these giants were very different from the stars we know today. They were formed out of pristine hydrogen and helium, with almost no “metal” (i.e. other elements) holding them back. They were also huge, …

Three OzGrav researchers have been awarded prestigious Australian Research Council (ARC) Future Fellowships, supporting ambitious research across fast radio bursts, gravitational waves and dark energy. Congratulations to Dr Manisha Caleb, Dr Daniel Reardon and Dr Cullan Howlett, who were named among the recipients of the 2026 Future Fellowships funding round. ARC Future Fellowships support outsta…

Learn how LIGO, Virgo, and KAGRA detect gravitational waves, what signals reveal about black holes, neutron stars, and our expanding universe. The post Gravitational Waves: Detection, Sources, and Science first appeared on .

When two black holes collide and merge, the newly formed black hole briefly “rings” like a bell. It sends gravitational waves through space at certain frequencies before the signal gradually fades away. Scientists call this final stage of the collision the ringdown. The ringdown may reveal more about black holes than researchers previously realized—including whether […] The post Black Holes May B…

When two black holes merge, the resulting object rings like a struck bell, radiating gravitational waves that fade in a distinctive pattern called ringdown. The post Physicists Devise New Way to Listen for ‘Hairy’ Black Holes appeared first on Sci.News: Breaking Science News .

Future gravitational wave observatories will be able to see the gravitational waves of close-orbiting binary stars. A newly studied white dwarf system could be one of the first systems we observe.

Pulsar Timing Arrays have been used to observe the background of gravitational waves in our galaxy. We aren't certain of their origin, but a new study shows a strong source could be early supermassive giants known as dark stars.

Gravitational waves are ripples in spacetime created when pairs of black holes spiral into each other and eventually merge. But if this ripple has been warped by another massive object on its way to Earth, a new analysis suggests that these black holes might appear far larger than they really are. In the analysis published […]

I know there are already a few of these questions on here. But the questions - and answers - seem to get lost in a discussion of coordinate systems and proper time. This is an attempt to set up the thought experiment in a way that doesn't require too much math and isn't embedded too deeply in a choice of coordinates. We have a sphere of some material with an equation of state that gives a strictl…

A new method maps the subtle gravitational wave vibrations produced by merging black holes, potentially enabling more precise tests of general relativity. When two black holes collide, the violence of the merger does not end immediately. The newly formed, larger black hole continues to ‘ring’ as it settles into a stable shape, and researchers have [...]

A deep, factual guide to kilonovae, GW170817, r-process element origins, and multi-messenger astronomy—gravitational waves, GRBs, and more. The post Kilonovae and GW170817: How Neutron Stars Forge Gold first appeared on .

During the earliest phases of star and planet formation, a young star is surrounded by a disc that can become gravitationally unstable. Indeed, if the protoplanetary disc is sufficiently massive, its self-gravity triggers the formation of large scale spiral arms, transporting angular momentum, trapping solid particles and, potentially, collapsing to form sub-stellar companions. In this paper, we …

In the standard picture of gravitational lensing, we have a picture like the one you can see as Figure 1 of this paper (I don't know if I can copy/paste it). In it, the source S and the observer O are both at a finite distance from the lens L, and both on the same side. Light curves a little bit around the lens, and an image is formed on the same side of the lens as the source. Now, in almost eve…

Dear experimental physics community! Below I present a significant result of quantum gravity demonstrated on 2 independent experimental channels . The codes are verifiable by anyone, using raw strain data from LIGO-Virgo-Kagra and Fermi/LAT, and include strict null tests to rule out the possibility of instrumental artifacts. The first pipeline (gravitational wave pipeline) produces 31.9 sigma on …

The ASTRID cosmological simulation has run from the Universe's early days up to the present day, z=0. ASTRID is larger than some other simulations, and smaller than others. But with a higher number of particles, it has higher-resolution than its fellows. Among other things, this can tell astronomers where to look for gravitational waves from black hole mergers with future GW observatories.

OzGrav Chief Investigator Distinguished Professor Susan Scott has been awarded the 2026 Harrie Massey Medal and Prize, one of Australian physics’ most prestigious honours.  The Australian Institute of Physics (AIP), jointly with the UK Institute of Physics (IoP), awarded Professor Scott the Medal in recognition of her “groundbreaking discoveries in the fields of general relativity, cosmology and …