Archive for the ‘cosmology’ category

May 16, 2023

Accretion disk around black holes recreated in the lab

Posted by in category: cosmology

Imperial College researchers have created a spinning disk of plasma in a lab, mimicking disks found around black holes and forming stars.

The experiment more accurately models what happens in these disks, which could help researchers discover how grow and how collapsing matter forms stars.

As matter approaches black holes it heats up, becoming plasma—a fourth state of matter consisting of charged ions and . It also begins to rotate, in a structure called an accretion disk. The rotation causes a pushing the plasma outwards, which is balanced by the gravity of the black hole pulling it in.

May 15, 2023

The Most Beautiful Strongly Bound Dibaryon

Posted by in categories: cosmology, particle physics

Dibaryons are subatomic particles composed of two baryons. Their formation, which occurs through interactions between baryons, is fundamental in big-bang nucleosynthesis, nuclear reactions including those happening within stars, and bridges the gap between nuclear physics, cosmology, and astrophysics. Fascinatingly, the strong force, responsible for the formation and the majority of the mass of nuclei, facilitates the formation of a plethora of different dibaryons with diverse quark combinations.

Nevertheless, these dibaryons are not commonly observed — the deuteron is currently the only known stable dibaryon.

To resolve this apparent dichotomy, it is essential to investigate dibaryons and baryon-baryon interactions at the fundamental level of strong interactions. In a recent publication in Physical Review Letters.

May 15, 2023

Scientists created a shining ring around the black hole in the lab

Posted by in category: cosmology

A spinning plasma ring mimics the rotating structure surrounding a black hole.

May 15, 2023

Astronomers spot largest cosmic explosion ever witnessed

Posted by in category: cosmology

Astronomers have spotted the largest cosmic explosion ever witnessed, and it’s 10 times brighter than any known exploding star, or supernova.

The brightness of the explosion, called AT2021lwx, has lasted for three years, while most supernovas are only bright for a few months.

The event, still being detected by telescopes, occurred nearly 8 billion light-years away from Earth when the universe was about 6 billion years old. The luminosity of the explosion is also three times brighter than tidal disruption events, when stars fall into supermassive black holes.

May 15, 2023

Quantum Computers Could Be a ‘Superhighway’ to Experiencing Our Other Selves in the Multiverse

Posted by in categories: computing, cosmology, quantum physics

It could be a strange way of achieving immortality—or at least, everlasting life for copies of you.

May 14, 2023

A Lab Plasma Rotates and Produces Jets

Posted by in categories: cosmology, evolution, physics

A spinning plasma ring mimics the rotating structure surrounding a black hole.

Astrophysicists have many questions about the so-called accretion disk that forms from plasma and other matter falling into a black hole. Now researchers have generated a rotating ring of plasma in an unconfined arrangement in the lab, which will enable more realistic studies of plasma in astrophysical disks [1]. The lab plasma also produced a jet perpendicular to the disk, as real black holes do. The experiment could provide a platform for testing theories describing the evolution of astrophysical disks.

According to observations, the matter in a black hole accretion disk spirals inward at a rate that is thousands of times faster than would be expected from turbulence-free rotation. The leading explanation involves turbulence generated in part by the interaction of magnetic fields with the plasma in the disk, but this theory is difficult to test without a lab plasma that rotates rapidly. Such an experimental system would also allow researchers to investigate accretion disks around massive objects other than black holes.

May 14, 2023

Panoramic Peek: Black Hole and Powerful Jet Unveiled in Stunning Detail

Posted by in category: cosmology

A panoramic image of the M87 black hole.

A black hole is a place in space where the gravitational field is so strong that not even light can escape it. Astronomers classify black holes into three categories by size: miniature, stellar, and supermassive black holes. Miniature black holes could have a mass smaller than our Sun and supermassive black holes could have a mass equivalent to billions of our Sun.

May 13, 2023

First-of-its-kind measurement of the universe’s expansion rate weighs in on a longstanding debate

Posted by in category: cosmology

Thanks to data from a magnified, multiply imaged supernova, a team led by University of Minnesota Twin Cities researchers has successfully used a first-of-its-kind technique to measure the expansion rate of the universe. Their data provide insight into a longstanding debate in the field and could help scientists more accurately determine the universe’s age and better understand the cosmos.

The work is divided into two papers, respectively published in Science and The Astrophysical Journal.

In astronomy, there are two precise measurements of the expansion of the universe, also called the “Hubble constant.” One is calculated from nearby observations of supernovae, and the second uses the “,” or radiation that began to stream freely through the universe shortly after the Big Bang.

May 13, 2023

Photographer’s Incredible ‘GigaMoon’ Image is Made From 280,000 Photos

Posted by in category: cosmology

Astrophotographer Andrew McCarthy has captured a “GigaMoon” — a 1.3-gigapixel highly-detailed image of the Moon made from 280,000 photos.

It’s an image that McCarthy has wanted to capture for a long time, with multiple attempts thwarted by poor conditions.

May 13, 2023

‘Runaway black hole,’ or sneaky galaxy in disguise? Experts are conflicted

Posted by in categories: cosmology, physics

The object’s gravity and velocity, the study suggested, would have ignited the gas and left a blazing trail of stars in its wake. This exciting discovery would mark the first observation of a rogue supermassive black hole — objects that are theorized to roam the universe after being ejected from their host galaxy, possibly due to collisions with other black holes.

Now, new research hints at a more mundane explanation.

The new study, published in the journal Astronomy & Astrophysics (opens in new tab), suggests that the weirdly thin streak might simply be a flat galaxy viewed on its edge, like the rim of a plate. Unlike the Milky Way, this supposed galaxy would not have a bulge of stars at its center but would be totally flat — a relatively common type of galaxy called a thin or flat galaxy.

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