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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...

Stars the mass of our Sun, and up to eight times more massive, evolve into red giants towards the end of their lives. Their outer layers puff up and expand millions of kilometres, their dusty, gassy shells blown away from the central star in relatively slow winds up to few hundreds of km/s. Even larger stars, up to 25–30 times more massive than the Sun, race through their fuel and explode in a supernova, sometimes leaving behind a spinning stellar corpse with a strong magnetic field, known as a neutron star. This tiny core packs the mass of nearly one...

Scientists have finally created an elusive particle known as the Shankar skyrmion, more than 40 years after it was first theorized. And, in the process, they may have modeled the rare phenomenon of ‘ball lightning’ on a quantum scale. Not only could the discovery help to explain the mysterious natural occurrence, which can appear as a sphere of electricity in the midst of storms, but the experts say it could pave the way for more stable plasma in fusion reactors. The three-dimensional particle consists of knots made from the spin fields of a Bose-Einstein condensate – or, atoms cooled to...

Astronomers have detected a signal from the first stars as they appeared and illuminated the universe, in observations that have been hailed as “revolutionary”.

In a clean room inside a clean room at NASA’s Kennedy Space Center, a petite telescope is perched on a stand for a final series of checkouts prior to launch. The extra fastidiousness is because the observatory’s four cameras will fly without protective covers—one of several simplifying design decisions made to help ensure the Transiting Exoplanet Survey Satellite, or TESS, will meet its goal of measuring the masses of at least 50 small, rocky and potentially Earth-like worlds as part of the first all-sky, exoplanet survey. TESS was proposed even before NASA’s planet-hunting Kepler space telescope, launched in 2009, demonstrated...

Physicists have insisted for a long time that black holes are impenetrable ciphers. Whatever goes in is lost, impossible to study or meaningfully understand. Some small amount of matter and energy might escape a black hole in the form of "Hawking radiation," but anything still inside the black hole is functionally disappeared from the physical universe. The idea is a basic premise of modern physics: If something falls into a black hole, it can't be contacted, it's future can't be predicted. No observer could possibly survive traveling into the dark space, not even long enough to glance around and notice...

314 Action Wants to Elect Scientists, But Only if They're Democrats The U.S. Congress is made up mostly of professional politicians and lawyers. This comes as a surprise to precisely no one, but the sheer numbers are rather striking.According to the Congressional Research Service (PDF, Table 2), the 115th Congress consists of 168 Representatives (out of 435) who are lawyers, and the Senate has 50 lawyers (out of 100). Combined, lawyers make up nearly 41% of Congress.How many lawyers are in the U.S.? One law firm (with a nifty interactive map!) estimates roughly 1.3 million. Given that the U.S. population...

Researchers create a hyperbolic metasurface on which light propagates with completely reshaped wafefronts Light waves usually disperse in cirular or convex wavefronts form, like ripples on water surface created by a stone. But now researchers have found that it is possible to alter light's wavefronts and to give them a completely new shape. To observe the waves as they propagate along the metasurface, researcher created a surface based on boron nitride. The material was selected because it has the ability to manipulate infrared light on extremely small length scales and it requires an extremely precise structuring on the nanometer scale...

(The Hubble Space Telescope captured this image of ancient and brilliant quasar 3C 273, which resides in a giant elliptical galaxy in the constellation of Virgo. Its light has taken some 2.5 billion years to reach us. Despite this great distance, it is still one of the closest quasars to our home. It was the first quasar ever to be identified, and was discovered in the early 1960s by astronomer Allan Sandage.) Shining so brightly that they eclipse the ancient galaxies that contain them, quasars are distant objects powered by black holes a billion times as massive as our...