БЛОГ

Archive for the ‘cosmology’ category: Page 136

Jan 27, 2022

Scientists make a new type of optical device using alumina

Posted by in categories: cosmology, physics

Scientists from the Kavli Institute for the Physics and Mathematics of the Universe and the University of Minnesota, Tomotake Matsumura and Shaul Hanany, and their collaborators have made a new type of optical element that will improve the performance of telescopes studying radiation from the Big Bang.

The (CMB) is a relic radiation remnant from the big bang. It reaches our telescopes after traveling 14 billion years since the birth of the Universe. Studying the properties of this radiation, scientists infer the physics of the , how clusters of galaxies form, and the matter and energy content in the Universe. Four Nobel prizes have been awarded for past studies of the CMB.

To study the CMB, telescopes must be tuned to wavelengths in which it is most intense, about 1–3 mm, and they must separate out shorter wavelength radiation that the atmosphere and Milky Way emit. Among the most effective optical elements that absorbs the short wavelength radiation but lets the CMB pass through is alumina, a material made of aluminum and oxygen and that is second in hardness only to diamond. One challenge with using alumina is that it also reflects almost 50% of the radiation impinging on it. Matsumura and Hanany have now come up with a new way to fabricate anti-reflective structures that reduce reflections fifty-fold.

Jan 27, 2022

What lies beyond the Standard Model?

Posted by in categories: cosmology, particle physics

Physicists must swing between crafting the mind-bending ideas about reality that make up theories and advancing technologies to the point where new experiments can test those theories. 2021 was a big year for advancing the experimental tools of physics.

First, the world’s largest particle accelerator, the Large Hadron Collider at CERN, was shut down and underwent some substantial upgrades. Physicists just restarted the facility in October, and they plan to begin the next data collection run in May 2022. The upgrades have boosted the power of the collider so that it can produce collisions at 14 TeV, up from the previous limit of 13 TeV. This means the batches of tiny protons that travel in beams around the circular accelerator together carry the same amount of energy as an 800,000-pound (360,000-kilogram) passenger train traveling at 100 mph (160 kph). At these incredible energies, physicists may discover new particles that were too heavy to see at lower energies.

Some other technological advancements were made to help the search for dark matter. Many astrophysicists believe that dark matter particles, which don’t currently fit into the Standard Model, could answer some outstanding questions regarding the way gravity bends around stars – called gravitational lensing – as well as the speed at which stars rotate in spiral galaxies. Projects like the Cryogenic Dark Matter Search have yet to find dark matter particles, but the teams are developing larger and more sensitive detectors to be deployed in the near future.

Jan 26, 2022

WSU Master Class: Inflationary Cosmology with Alan Guth

Posted by in categories: cosmology, physics

Breakthrough Prize winner Alan Guth developed the theory of inflation to answer to our cosmic origins. It’s one of the most studied and debated theories in cosmology, with research propelling Guth’s work to the forefront of scientific conversation.

In this Master Class, Professor Guth addresses what experiments could potentially rule out the BICEP2 results. Since recording this in 2017, the Planck spacecraft collected the data that Professor Guth anticipated, which shows that the initial observations were likely an artifact of interstellar dust, not primordial gravitational waves.

Continue reading “WSU Master Class: Inflationary Cosmology with Alan Guth” »

Jan 26, 2022

Astronomers detect powerful cosmic object unlike anything they’ve seen before

Posted by in category: cosmology

It blinks too fast to be a supernova and too slow to be a pulsar. So what in the cosmos is it?

Jan 26, 2022

Laniakea, our local supercluster, is being destroyed

Posted by in categories: cosmology, particle physics

On the largest cosmic scales, planet Earth appears to be anything but special. Like hundreds of billions of other planets in our galaxy, we orbit our parent star; like hundreds of billions of solar systems, we revolve around the galaxy; like the majority of galaxies in the Universe, we’re bound together in either a group or cluster of galaxies. And, like most galactic groups and clusters, we’re a small part of a larger structure containing over 100,000 galaxies: a supercluster. Ours is named Laniakea: the Hawaiian word for “immense heaven.”

Superclusters have been found and charted throughout our observable Universe, where they’re more than 10 times as rich as the largest known clusters of galaxies. Unfortunately, owing to the presence of dark energy in the Universe, these superclusters ⁠— including our own ⁠— are only apparent structures. In reality, they’re mere phantasms, in the process of dissolving before our very eyes.

The Universe as we know it began some 13.8 billion years ago with the Big Bang. It was filled with matter, antimatter, radiation, etc.; all the particles and fields that we know of today, and possibly even more. From the earliest instants of the hot Big Bang, however, it wasn’t simply a uniform sea of these energetic quanta. Instead, there were tiny imperfections ⁠— at about the 0.003% level ⁠— on all scales, where some regions had slightly more or slightly less matter and energy than average.

Jan 25, 2022

Researchers detect 1st merger between black holes with eccentric orbits

Posted by in categories: computing, cosmology, physics

Using hundreds of computer simulations, the researchers found that the gravitational wave signals from GW150521 are best explained by a high-eccentricity, according to the statement.

The study also sheds new light on how some of the black hole mergers detected by the Laser Interferometer Gravitational-wave Observatory (LIGO) and its European counterpart, Virgo, are so much heavier than previously thought possible. Their findings were published Jan. 20 in the journal Nature Astronomy.

Jan 25, 2022

Studying the big bang with artificial intelligence

Posted by in categories: cosmology, information science, mathematics, particle physics, quantum physics, robotics/AI

It could hardly be more complicated: tiny particles whir around wildly with extremely high energy, countless interactions occur in the tangled mess of quantum particles, and this results in a state of matter known as “quark-gluon plasma”. Immediately after the Big Bang, the entire universe was in this state; today it is produced by high-energy atomic nucleus collisions, for example at CERN.

Such processes can only be studied using high-performance computers and highly complex computer simulations whose results are difficult to evaluate. Therefore, using artificial intelligence or machine learning for this purpose seems like an obvious idea. Ordinary machine-learning algorithms, however, are not suitable for this task. The mathematical properties of particle physics require a very special structure of neural networks. At TU Wien (Vienna), it has now been shown how neural networks can be successfully used for these challenging tasks in particle physics.

Jan 25, 2022

Extraordinary Black Hole — Unlike Any Other — Discovered in Neighboring Galaxy

Posted by in category: cosmology

The discovery, one of the only confirmed intermediate-mass black holes, lives in an equally rare object known as a low-mass, stripped nucleus.

Astronomers discovered a black hole unlike any other. At one hundred thousand solar masses, it is smaller than the black holes we have found at the centers of galaxies, but bigger than the black holes that are born when stars explode. This makes it one of the only confirmed intermediate-mass black holes, an object that has long been sought by astronomers.

“We have very good detections of the biggest, stellar-mass black holes up to 100 times the size of our sun, and supermassive black holes at the centers of galaxies that are millions of times the size of our sun, but there aren’t any measurements of black between these. That’s a large gap,” said senior author Anil Seth, associate professor of astronomy at the University of Utah and co-author of the study. “This discovery fills the gap.”

Jan 23, 2022

Spaceship Neptune Is the Low-Tech, Cheaper Way to Reach the Edge of Space

Posted by in categories: cosmology, space travel

Science fiction literature is filled with strange ideas about how to travel to space and in it. We’ve got anything from hyperloops to wormholes and space elevators, strings, FTL-capable ships, and even the crown jewel of instant transport, teleportation. I know this because I really, really enjoy sci-fi.

Jan 22, 2022

Taming the multiverse: Stephen Hawking’s final theory about the big bang

Posted by in categories: cosmology, physics

Professor Stephen Hawking’s final theory on the origin of the universe, which he worked on in collaboration with Professor Thomas Hertog from KU Leuven, was published in 2018 in the Journal of High Energy Physics.