Gravitational Waves Reveal Surprising Secrets About Neutron Stars

The confirmation of gravitational waves back in 2017 continues to unlock whole new worlds of physics but also continues to elicit further questions.  The detection of each gravitational wave brings a new challenge – how to find out what caused the event.  Sometimes that is harder than it sounds.  Now a team led by Alejandro Vigna-Gomez of the University of Copenhagen thinks they found a model of star death that helps to explain some previously inexplicable findings – and points to a galaxy with many more massive neutron stars than previously thought.

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Gravitational-Wave Observatories Should be Able to Detect Primordial Black Hole Mergers, if They’re out There

The tumultuous era of the big bang may have been chaotic enough to flood the universe with primordial black holes. Eventually some of those black holes will find each other and merge, sending out ripples of gravitational waves. A comprehensive search for those gravitational wave signatures hasn’t found anything, putting tight constraints on the abundance of these mysterious objects.

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Next-Generation Gravitational Wave Observatories Could Detect the First Stars When They Exploded as Supernovae

From the Ashes of the First Stars

The first stars to appear in the universe are no longer with us – they died long ago. But when they died they released torrents of gravitational waves, which might still be detectable as a faint hum in the background vibrations of the cosmos.

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On its Next run, LIGO Will be Able to Probe 8 Times as Much Space

Materials science has once again come through for space exploration.  Researchers at the Laser Interferometer Gravitational-Wave Observatory (LIGO) have developed a coating that could increase the sensitivity of LIGO by almost an order of magnitude.  That would increase the detection rate of the gravitational waves the observatory is seeking from about once a week to once a day, mainly due to the increased volume of space that the observatory’s interferometers would be able to collect signals from.

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Neutron Stars Have Mountains, They’re Just a Fraction of a Millimeter High

The universe has some very extreme places in it – and there are few places more extreme than the surface of a neutron star.  These ultradense objects form after a supergiant star collapses into a sphere about 10 kilometers (6 miles) in diameter.  Their surface is extreme because of the gravity, which is about a billion times stronger than Earth. However, that gravity also forces the stellar remnant to be extraordinarily flat.  Just how flat is the outcome of a new set of theoretical research by PhD student Fabian Gittins from the University of Southampton. 

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Gravitational-Wave Detector Could Sense Merging Primordial Black Holes With the Mass of a Planet, Millions of Light-Years Away

Gravitational-wave detectors have been a part of astronomy for several years now, and they’ve given us a wealth of information about black holes and what happens when they merge. Gravitational-wave astronomy is still in its infancy, and we are still very limited in the type of gravitational waves we can observe. But that could change soon.

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Black Hole-Neutron Star Collisions Could Finally Settle the Different Measurements Over the Expansion Rate of the Universe

If you’ve been following developments in astronomy over the last few years, you may have heard about the so-called “crisis in cosmology,” which has astronomers wondering whether there might be something wrong with our current understanding of the Universe. This crisis revolves around the rate at which the Universe expands: measurements of the expansion rate in the present Universe don’t line up with measurements of the expansion rate during the early Universe. With no indication for why these measurements might disagree, astronomers are at a loss to explain the disparity.

The first step in solving this mystery is to try out new methods of measuring the expansion rate. In a paper published last week, researchers at University College London (UCL) suggested that we might be able to create a new, independent measure of the expansion rate of the Universe by observing black hole-neutron star collisions.

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One Idea to Explain Dark Matter – Ultralight Bosons – Fails the Test

Dark matter continues to resist our best efforts to pin it down. While dark matter remains a dominant theory of cosmology, and there is lots of evidence to support a universe filled with cold dark matter, every search for dark matter particles yields nothing. A new study continues that tradition, ruling out a range of dark matter candidates.

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You Thought Black Hole Event Horizons Looked Strange. Check out Binary Black Hole Event Horizons

One of the strangest predictions of general relativity is that gravity can deflect the path of light. The effect was first observed by Arthur Eddington in 1919. While the bending effect of the Sun is small, near a black hole light deflection can be significant. So significant that you need a powerful supercomputer to calculate how light will behave.

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