Archive for the ‘cosmology’ category: Page 254

Mar 11, 2017

Supermassive Black Holes might Be Hiding Entire Universes Inside

Posted by in category: cosmology

Bubbles of space-time cropped up during the early stages of our cosmos, ultimately forming black holes that were connected to us by wormholes according to a new theory. Research displays that these bubbles ultimately lost energy, and collapsed into a black hole that was so big, it produced its own universe inside – linked to us by the secret door.

These wormholes would have been very short-lived – no more than fractions of a second. During that time, our universe would have been linked to a vast multiverse – loads of other universes. Andrei Linde told New Scientist: “This subject is actually, really deep. We are just starting to touch the surface and find new things about the multiverse.”

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Mar 9, 2017

Scientists May Have Solved the Biggest Mystery of the Big Bang

Posted by in categories: cosmology, particle physics

The European Council for Nuclear Research (CERN) works to help us better understand what comprises the fabric of our universe. At this French association, engineers and physicists use particle accelerators and detectors to gain insight into the fundamental properties of matter and the laws of nature. Now, CERN scientists may have found an answer to one of the most pressing mysteries in the Standard Model of Physics, and their research can be found in Nature Physics.

According to the Big Bang Theory, the universe began with the production of equal amounts of matter and antimatter. Since matter and antimatter cancel each other out, releasing light as they destroy each other, only a minuscule number of particles (mostly just radiation) should exist in the universe. But, clearly, we have more than just a few particles in our universe. So, what is the missing piece? Why is the amount of matter and the amount of antimatter so unbalanced?

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Mar 1, 2017

Rapid changes point to origin of ultra-fast black hole ‘burps’

Posted by in category: cosmology

Gas outflows are common features of active supermassive black holes that reside in the center of large galaxies. Millions to billions of times the mass of the Sun, these black holes feed on the large disks of gas that swirl around them. Occasionally the black holes eat too much and burp out an ultra-fast wind, or outflow. These winds may have a strong influence on regulating the growth of the host galaxy by clearing the surrounding gas away and suppressing star formation.

Scientists have now made the most detailed observation yet of such an outflow, coming from an active galaxy named IRAS 13224–3809. The outflow’s temperature changed on time scales of less than an hour, which is hundreds of times faster than ever seen before. The rapid fluctuations in the outflow’s temperature indicated that the outflow was responding to X-ray emissions from the accretion disk, a dense zone of gas and other materials that surrounds the black hole.

The new observations are published in the journal Nature on March 2, 2017.

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Mar 1, 2017

Team puts dark matter on the map

Posted by in categories: cosmology, particle physics

A Yale-led team has produced one of the highest-resolution maps of dark matter ever created, offering a detailed case for the existence of cold dark matter—sluggish particles that comprise the bulk of matter in the universe.

The dark matter map is derived from Hubble Space Telescope Frontier Fields data of a trio of galaxy clusters that act as cosmic magnifying glasses to peer into older, more distant parts of the , a phenomenon known as .

Yale astrophysicist Priyamvada Natarajan led an international team of researchers that analyzed the Hubble images. “With the data of these three lensing clusters we have successfully mapped the granularity of dark matter within the clusters in exquisite detail,” Natarajan said. “We have mapped all of the clumps of dark matter that the data permit us to detect, and have produced the most detailed topological map of the dark matter landscape to date.”

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Feb 26, 2017

Fermi finds possible dark matter ties in Andromeda galaxy

Posted by in categories: cosmology, particle physics, space travel

NASA’s Fermi Gamma-ray Space Telescope has found a signal at the center of the neighboring Andromeda galaxy that could indicate the presence of the mysterious stuff known as dark matter. The gamma-ray signal is similar to one seen by Fermi at the center of our own Milky Way galaxy.

Gamma rays are the highest-energy form of light, produced by the universe’s most energetic phenomena. They’re common in galaxies like the Milky Way because , particles moving near the speed of light, produce when they interact with and starlight.

Surprisingly, the latest Fermi data shows the gamma rays in Andromeda—also known as M31—are confined to the galaxy’s center instead of spread throughout. To explain this unusual distribution, scientists are proposing that the emission may come from several undetermined sources. One of them could be , an unknown substance that makes up most of the universe.

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Feb 25, 2017

If You Can’t Find Dark Matter, Look First for a Dark Force

Posted by in categories: cosmology, particle physics

While cosmologists may be fascinated by what dark matter does, particle physicists are fascinated by what dark matter is. For us, dark matter should be—naturally—a particle, albeit one that is still lurking hidden in our data. For the last few decades, we’ve had a tantalizing guess as to what this particle might be—namely, the lightest of a new class of supersymmetric particles. Supersymmetry is an extension to the Standard Model of particles and forces that nicely addresses lingering questions about the stability of the mass of the Higgs boson, the unification of the forces, and the particle nature of dark matter. In fact, supersymmetry predicts a vast number of new particles—one for each particle we already know about. Yet while one of those new particles could constitute dark matter, to many of us that would be just a happy byproduct.

But after analyzing data from the first (2010–2012) and second (2015–2018) runs of the Large Hadron Collider (LHC), we haven’t found supersymmetric particles yet—indeed, no new particles at all, beyond the Higgs boson. So, while we continue to hunt for supersymmetry, we’re also taking a fresh look at what our cosmology colleagues can tell us about dark matter. It is the strongest experimental evidence for new physics beyond the Standard Model, after all.

In fact, some might say that a principal goal of the LHC and future colliders will be to create and study dark matter. For that to happen, there must be a means for the visible universe and the dark universe to communicate with each other. In other words, the constituents of the particles that we collide must be capable of interacting with the putative dark-matter particles via fundamental forces. A force requires a force carrier, or boson. The electromagnetic force is carried by the photon, the weak nuclear force by so-called vector bosons, and so on. Interactions between dark matter and normal matter should be no different: They could happen by exchanging dark bosons.

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Feb 23, 2017

A Potential Dark Matter Signature Has Been Seen in The Andromeda Galaxy

Posted by in categories: cosmology, particle physics

NASA’s Fermi Telescope has looked at the gamma-ray emission of M31, the Andromeda Galaxy, and discovered the largest fraction of this powerful radiation comes from the core of the galaxy, very much like in our own Milky Way. The international team of researchers has considered this signature as potential indirect evidence of dark matter.

Some theoretical models predict gamma-ray emissions when dark matter particles interact with each other. Dark matter doesn’t like interacting at all, it doesn’t form clumps or clouds, so these gamma-ray signals might only happen in dense regions, like at the core of galaxies.

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Feb 20, 2017

Scientists might be just weeks away from taking the first real picture of a black hole

Posted by in category: cosmology

Twenty years after the project began, scientists think they are now just weeks away from receiving their first picture of a black hole.

The numbers behind the creation of the Event Horizon Telescope (EHT) are mind boggling enough, let alone the thought of what it might see on April 5 when it’s trained on Sagittarius A*, the supermassive black hole at the centre of our galaxy.

It’s 26,000 light years from Earth. Even though its “edge” is 20-odd million kilometres across, EHT team members say seeing it is still like trying to pinpoint a grapefruit on the Moon.

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Feb 16, 2017

Scientists Are About to Switch on a Telescope That Could Photograph a Black Hole’s Event Horizon

Posted by in category: cosmology

Black holes are among the most fascinating objects in the known Universe. But despite the fact that they’re suspected to lurk at the centre of most galaxies, the reality is that no one has ever been able to actually photograph one.

That’s because black holes, as their name implies, are very, very dark. They’re so massive that they irreversibly consume everything that crosses their event horizon, including light, making them impossible to photograph. But that could be about to change, when a new telescope network switches on in April this year.

Called the Event Horizon Telescope, the new device is made up of a network of radio receivers located across the planet, including at the South Pole, in the US, Chile, and the French alps.

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Feb 14, 2017

Brand New Maths Could Finally Explain How Disturbances Propagate Through Space-Time

Posted by in categories: cosmology, mathematics, physics

The Universe as we know it is made up of a continuum of space and time — a space-time fabric that’s curved by massive objects such as stars and black holes, and which dictates the movement of matter.

Thanks to Einstein’s gravitational waves, we know disturbances can propagate through both space and time. But what’s less understood is exactly how that happens when properties of the fabric is continuously shifting.

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