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New insights into the properties of neutron stars have come from two independent analyses of gravitational waves from the GW170817 neutron-star merger. The work was done by teams led by Farrukh Fattoyev at Indiana University Bloomington and Eemeli Annala at the University of Helsinki. The teams used different methods to calculate the relationship between the radius and mass of neutron stars and came up with the same result. In October 2017 the LIGO and Virgo detectors made the first-ever observation of gravitational waves from two neutron stars as they spiralled into each other and then merged to form a black...

Cracks in the universe: the search for cosmic strings Galaxy-sized filaments of raw energy may be threaded through spacetime, according to some theories. Will we ever find traces of them? Cathal O’Connell takes up the hunt. Share Tweet Tatyun / Getty Images Our universe exploded into being, expanded at a fantastic speed and cooled. Perhaps too quickly. Some physicists believe the rapid cooling might have cracked the fabric of the universe.These hairline fractures may still be threaded through space-time. Dubbed cosmic strings, mathematical models see them as invisible threads of pure energy, thinner than an atom but light-years long. The...

A German mathematician, physicist and astronomer, Johann Carl Friedrich Gauss rose from humble origins to become one of the world’s greatest minds. Born in 1777 in Brunswick, then part of the Holy Roman Empire, Gauss was the only child of poor parents who had received little or no formal education. His mother was illiterate. But when Gauss started school at age seven, he was quickly recognized as a child prodigy who could solve complex math problems in his head. While still a teenager, Gauss became the first person to prove the Law of Quadratic Reciprocity, a math theory to determine...

Is Bitcoin a greed-driven fad or will the blockchain technology that underlies it revolutionize the internet? Will artificial intelligence produce a world of ease and plenty or turn on us and kill us all? Is that jet pack you always wanted arriving any day now, or basically never?There are no shortage of people who make their livings by claiming to have answers to these questions. You should probably meet their claims with a healthy dose of skepticism.Futurists aren't all snake oil salesmen, of course, and it's sensible for both individuals and businesses to think ahead and develop contingency plans for possible future...

Every generation tends to believe that its views on the nature of reality are either true or quite close to the truth. We are no exception to this: although we know that the ideas of earlier generations were each time supplanted by those of a later one, we still believe that this time we got it right. Our ancestors were naïve and superstitious, but we are objective—or so we tell ourselves. We know that matter/energy, outside and independent of mind, is the fundamental stuff of nature, everything else being derived from it—or do we? In fact, studies have shown that...

At 13.8 billion years ago, our entire observable universe was the size of a peach and had a temperature of over a trillion degrees. That's a pretty simple, but very bold statement to make, and it's not a statement that's made lightly or easily. Indeed, even a hundred years ago, it would've sounded downright preposterous, but here we are, saying it like it's no big deal. But as with anything in science, simple statements like this are built from mountains of multiple independent lines of evidence that all point toward the same conclusion — in this case, the Big Bang,...

"We Truly Don't Know What It Is" --Mystery Milky-Way Spectrum of Light Observed 'Not Produced By Any Known Emission' April 17, 2018   "We use special telescopes to catch X-ray light in the sky, and while looking at these X-rays, the telescopes noticed an unexpected feature and captured a spectrum of light, which is not produced by any known atomic emission," said University of Miami astrophysicist Nico Cappelluti. "This emission line is now called the 3.5 kiloelectron volt (keV). One interpretation of this emission line is that it's produced by the decay of dark matter." "This 3.5 keV emission line is...

The dominant explanation of the formation of star and galaxy clusters is flawed and misrepresents the nature of time, a team of Brazilian researchers claim, in a new study that uses simulations to explain a long-standing paradox in a process called ‘violent relaxation’. Clusters of stars and galaxies are tight groups of celestial bodies shackled together by gravity. Star clusters contain up to one million stars with a common origin and are up to 30 light-years across, while collections of galaxies are among the largest structures in the Universe, composed of up to 1000 galaxies with a mass of a...

How to Listen to the Background Hum of Gravitational Waves From all the Black Holes Colliding into Each Other Article written: 18 Apr , 2018 by Matt Williams The first-ever detection of gravitational waves (which took place in September of 2015) triggered a revolution in astronomy. Not only did this event confirm a theory predicted by Einstein’s Theory of General Relativity a century before, it also ushered in a new era where the mergers of distant black holes, supernovae, and neutron stars could be studied by examining their resulting waves.In addition, scientists have theorized that black hole mergers could actually...

What does it really mean to say that time ‘passes’? Why does time pass faster in the mountains than it does at sea level? The physicist explains in this extract from his latest book I stop and do nothing. Nothing happens. I am thinking about nothing. I listen to the passing of time. This is time, familiar and intimate. We are taken by it. The rush of seconds, hours, years that hurls us towards life then drags us towards nothingness ... We inhabit time as fish live in water. Our being is being in time. Its solemn music nurtures us,...

When the Hubble Space Telescope took a photo of distant galaxy cluster SDSS J0146-0929, it was able to capture an immensely massive blanket of hundreds of galaxies caught in each other's gravitational pulls. In the photo, they look no more than inconsequential space dust: tiny, motionless, and remote. But in fact, the combined mass of these galaxies is so great that it causes a distortion in the fabric of space and time. That is represented by a glowing ring in the center of the image, which is actually a phenomenon called gravitational lensing. The circle of light, called the...

The discovery of NGC 1052-DF2 has led scientists on the quest for more dark matter-deficient galaxies. What really makes up the rare and mysterious DF2 galaxy? Dark matter supposedly composes 27 percent of the cosmos, but the newly discovered DF2 galaxy, has none of it. New Galaxy In TownScientists researching ultra-diffuse galaxies have spotted a large, sparse galaxy in the northern constellation of Cetus. The mysterious galaxy is almost as big as the Milky Way but has only 1 percent of its stars. The galaxy is almost empty except for densely clustered stars moving very slow at an estimate of...

A combination of data-churning telescopes and proprietary algorithms has led to a slate of opaque research that has some astronomers concerned. When astronomer Kai Polsterer’s laptop was stolen, the thieves made off with more than hardware. The laptop contained Polsterer’s only copy of a collection of thousands of stars and galaxies, a sample that a computer algorithm had randomly selected from a data set consisting of millions of celestial objects. Because Polsterer could not re-create what the algorithm had done, he could not exactly reproduce his data set for a work-in-progress journal article. And without a data set, nobody could...

Hundreds of billions of stars make up the barred spiral galaxy that we call home. The Milky Way’s 100,000 light-year diameter houses stars of different masses, luminosities, and ages, with new stars constantly being added to the mix. Star formation isn’t showing signs of slowing down, and this includes births at the outer edges of the galaxy. Could these young stars forming near the galactic edge be expanding the size of the Milky Way? A team of researchers, led by Ph.D. candidate Cristina Martínez-Lombilla of the Instituto de Astrofísica de Canarias in Spain, presented research supporting this idea at the...

There are stars too faint to see in the night sky just a few light years away, yet a chance cosmic event gave us a glimpse of a star that would have otherwise been completely invisible due to its immense distance from Earth—a whopping 9 billion light-years away. A paper today in Nature Astronomy reports the discovery of the star, called MACS J1149 Lensed Star 1, or Icarus informally. Finding such a distant star is normally a tall order, but a larger object happened to pass in front of its home galaxy. When a large object passes in front of...

[Physics] has a reputation for being extremely complicated, but sometimes the simplest questions that lead to truly profound and obvious insights. When Einstein asked himself, “What would happen if you could ride on a beam of light?” for example, the answer led him to the Special Theory of Relativity.  He concluded that the speed of light was constant. Taylor Momsen was touring with her band The Pretty Reckless and they stopped on the side of the road so some of the band members could relieve themselves.  One of the band members, the drummer Jonathan Burger, was the nephew of  physicist...

Using the Hubble Space Telescope astronomers have discovered a nearby galaxy that apparently has little or no evidence of dark matter. The unique galaxy, called NGC 1052-DF2, contains at most 1/400th the amount of dark matter that astronomers had expected. The galaxy is as large as our Milky Way, but it had escaped attention because it contains only 1/200th the number of stars.

Here's a problem: The universe acts like it's a lot more massive than it looks. Take galaxies, those giant, spinning masses of stars. The laws of motion and gravity tell us how fast these objects should turn given their bulk. But observations through telescopes show them spinning way faster than we'd expect, as if they were actually much more massive than the stars we can see indicate. Astrophysicists have come up with two main solutions to this problem. Either there's a lot of mass out there in the universe that we can't detect directly, mass scientists call dark matter, or there's no...

The Difficult Birth of the "Many Worlds" Interpretation of Quantum Mechanics Hugh Everett, creator of this radical idea during a drunken debate more than 60 years ago, died before he could see his theory gain widespread popularity   By Adam Becker on March 21, 2018 Share on Facebook Share on Twitter Share on Reddit Email Print Share via Google+Stumble Upon Credit: Garik Barseghyan Pixabay Over several rounds of sherry late one night in the fall of 1955, the Danish physicist Aage Petersen debated the mysteries at the heart of quantum physics with two graduate students, Charles Misner and Hugh Everett, at Princeton University. Petersen was defending the...

A simple illustration of the concept of driving something out of equilibrium to increase its stability is the well-known trick of making an inverted broom stand up on the palm of your hand or on one of your fingertips,’ said Ale Lukaszew, DARPA program manager. ‘If you hold your hand still, the broom is unstable and will fall over quickly. But if you drive the broom out of equilibrium by moving your hand around periodically, you can make the broom very stable, so it remains upright indefinitely.’ Particles in a quantum state are very sensitive to their environment. With the...