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Archive for the ‘cosmology’ category: Page 349

Aug 29, 2018

Ancient ‘Monster Galaxy’ Is Forming Stars a Thousand Times Faster Than the Milky Way

Posted by in category: cosmology

Chile’s Atacama Large Millimeter/submillimeter Array (ALMA) has observed a galaxy that looks nothing like what researchers expected. It’s forming stars at an absolutely incredible rate.

The “Monster Galaxy”, also known as COSMOS-AzTEC-1, formed just 2 billion years after the Big Bang, and it turns more than a thousand Suns worth of gas into stars each year. Scientists still don’t understand these early galaxies very well, but now they have some new information that can shed light on why they form stars so blisteringly fast.

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Aug 28, 2018

Scientists may have discovered the very first ‘ghost’ black hole from a different universe

Posted by in category: cosmology

It’s common knowledge that, because of the speed at which light travels, we can see things in space that aren’t even there anymore. If we peer at a distant galaxy we’re really only seeing what the objects within it looked like when the light itself was beaming in our direction. If the galaxy is a thousand light-years away, we’re seeing what the galaxy looked like a thousand years ago.

Now, researchers believe that they may be able to use a similar technique to search for black holes that don’t exist anymore. The only difference is that the black holes aren’t just from long ago, they’re from an entirely different version of the universe. Woah.

A research team comprised of scientists from Oxford University, the University of Warsaw, and the New York Maritime College, believe they have evidence that points to the leftovers of a black hole that existed in a universe that preceded the one we’re currently living in. However, rather than visible light, the black holes leave behind what is known as cosmic microwave background radiation, or (CMB).

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Aug 27, 2018

To Test Einstein’s Equations, Poke a Black Hole

Posted by in categories: cosmology, information science, mathematics

Researchers make significant progress toward proving a critical mathematical test of the theory of general relativity.

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Aug 27, 2018

The Physics of Falling Into a Black Hole

Posted by in categories: cosmology, physics

This week, newspapers reported that a man had fallen into an art installation consisting of an 8-foot-deep circular hole painted black. It’s kinda not his fault.

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Aug 27, 2018

What Is Nothing? Martin Rees Q&A

Posted by in categories: cosmology, physics

This article was originally published at The Conversation. The publication contributed the article to Space.com’s Expert Voices: Op-Ed & Insights.

Philosophers have debated the nature of “nothing” for thousands of years, but what has modern science got to say about it? In an interview with The Conversation, Martin Rees, Astronomer Royal and Emeritus Professor of Cosmology and Astrophysics at the University of Cambridge, explains that when physicists talk about nothing, they mean empty space (vacuum). This may sound straightforward, but experiments show that empty space isn’t really empty – there’s a mysterious energy latent in it which can tell us something about the fate of the universe.

Rees was interviewed for The Conversation’s Anthill podcast on Nothing. This Q&A is based on an edited transcript of that interview.

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Aug 22, 2018

Physicists Think They’ve Spotted the Ghosts of Black Holes from Another Universe

Posted by in categories: cosmology, physics

Weird patches of the sky where the cosmic microwave background radiation looks funny could be signs of long-dead universes, physicist Roger Penrose said.

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Aug 18, 2018

A supermassive black hole used its powerful gravity to rip apart a star that wandered too close to the massive monster

Posted by in category: cosmology

Astronomers used radio & infrared telescopes to image the distant eruption of this cosmic duel. Details: https://go.nasa.gov/2JMkZWF

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Aug 17, 2018

The Universe’s Oldest Galaxies Could Be Right in the Milky Way’s Backyard

Posted by in category: cosmology

The Universe’s earliest epochs appear to be written into the small dwarf galaxies orbiting our own galactic home, the Milky Way.

A team of researchers studying dark matter noticed a strange trend in the brightness of the satellite galaxies around the Milky Way. There seem to be two classes of these orbiting dwarf galaxies—dim ones and bright ones—with few in the middle range. The researchers propose that this kink, when viewed on a graph, could be explained by a period early on in the Universe’s history called the re-ionization era.

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Aug 17, 2018

Another way for stellar-mass black holes to grow larger

Posted by in categories: cosmology, physics

A trio of researchers with The University of Hong Kong, Academia Sinica Institute of Astronomy and Astrophysics in Taiwan and Northwestern University in the U.S., has come up with an alternative theory to explain how some stellar-mass black holes can grow bigger than others. In their paper published in The Astrophysical Journal Letters, Shu-Xu Yi, K.S. Cheng and Ronald Taam describe their theory and how it might work.

Since the initial detection of gravitational waves three years ago, five more detections have been observed—and five of the total have been traced back to emissions created by two stellar-mass black holes merging. The sixth was attributed to neutron stars merging. As part of their studies of such detections, space researchers have been surprised by the size of the stellar-mass black holes producing the gravity waves—they were bigger than other stellar-mass black holes. Their larger size has thus far been explained by the that they grew larger because they began their lives as stars that contained very small amounts of metal—stars with traces of metals would retain most of their mass because they produce weaker solar winds. In this new effort, the researchers suggest another possible way for stellar-mass black holes to grow larger than normal.

The new theory starts out by noting that some at the hearts of galaxies are surrounded by a disk of gas and dust. In such galaxies, there are often stars lying just outside the disk—stars that could evolve to become stellar-mass black holes. The researchers suggest that it is possible that sometimes, pairs of these stars wind up in the disk as they evolve into black holes. Such stellar-mass black holes would pull in material from the disk, causing them to grow larger. The researchers note that if such a scenario were to play out, it is also possible that the two merging could wind up with a synchronized spin resulting in a stellar-mass black hole that produces more gravity waves than if the spins had not been synchronized, making them easier for researchers to spot.

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Aug 15, 2018

This one particle could solve five mega-mysteries of physics

Posted by in categories: cosmology, particle physics

Forget the Higgs: theorists have uncovered a missing link that explains dark matter, what happened in the big bang and more. Now they’re racing to find it.

By Michael Brooks

911? It’s an emergency. The most important particle in the universe is missing. Florian Goertz knows this isn’t a case for the police, but he is still waiting impatiently for a response. This 911 isn’t a phone number, but a building on the northern edge of the world’s biggest particle accelerator.

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