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Archive for the ‘cosmology’ category: Page 8

Jul 27, 2021

Laser pincers generate antimatter

Posted by in categories: climatology, cosmology, particle physics

Some of the greatest mysteries in cosmology revolve around antimatter, and it’s hard to study because it’s rare and hard to produce in the lab. Now a team of physicists has outlined a relatively simple new way to create antimatter, by firing two lasers at each other to reproduce the conditions near a neutron star, converting light into matter and antimatter.

In principle, antimatter sounds simple – it’s just like regular matter, except its particles have the opposite charge. That basic difference has some major implications though: if matter and antimatter should ever meet, they will annihilate each other in a burst of energy. In fact, that should have destroyed the universe billions of years ago, but obviously that didn’t happen. So how did matter come to dominate? What tipped the scales in its favor? Or, where did all the antimatter go?

Unfortunately, antimatter’s scarcity and instability make it difficult to study to help answer those questions. It’s naturally produced under extreme conditions, such as lightning strikes, or near black holes and neutron stars, and artificially in huge facilities like the Large Hadron Collider.

Jul 27, 2021

German X-ray space telescope captures most complete map of black holes ever

Posted by in category: cosmology

The first science from the eROSITA space observatory is here.


The German-built eROSITA space telescope is creating the most detailed map of the distribution of black holes and neutron stars in the Universe, having discovered over two million such new objects in the two years since its launch in 2019.

Jul 25, 2021

Look: Scientists imaged an intensely powerful force coming from a black hole

Posted by in categories: cosmology, materials

These jets blast material at nearly the speed of light.


Researchers obtained the highest resolution images yet of eruptive jets streaming from a black hole. These findings were published in “Nature Astronomy.”

Jul 23, 2021

Antimatter from laser pincers

Posted by in categories: cosmology, particle physics

In the depths of space, there are celestial bodies where extreme conditions prevail: Rapidly rotating neutron stars generate super-strong magnetic fields. And black holes, with their enormous gravitational pull, can cause huge, energetic jets of matter to shoot out into space. An international physics team with the participation of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has now proposed a new concept that could allow some of these extreme processes to be studied in the laboratory in the future: A special setup of two high-intensity laser beams could create conditions similar to those found near neutron stars. In the discovered process, an antimatter jet is generated and accelerated very efficiently. The experts present their concept in the journal Communications Physics.

The basis of the new concept is a tiny block of plastic, crisscrossed by micrometer-fine channels. It acts as a target for two lasers. These simultaneously fire ultra-strong pulses at the block, one from the right, the other from the left — the block is literally taken by laser pincers. “When the laser pulses penetrate the sample, each of them accelerates a cloud of extremely fast electrons,” explains HZDR physicist Toma Toncian. “These two electron clouds then race toward each other with full force, interacting with the laser propagating in the opposite direction.” The following collision is so violent that it produces an extremely large number of gamma quanta — light particles with an energy even higher than that of X-rays.

The swarm of gamma quanta is so dense that the light particles inevitably collide with each other. And then something crazy happens: According to Einstein’s famous formula E=mc2, light energy can transform into matter. In this case, mainly electron-positron pairs should be created. Positrons are the antiparticles of electrons. What makes this process special is that “very strong magnetic fields accompany it,” describes project leader Alexey Arefiev, a physicist at the University of California at San Diego. “These magnetic fields can focus the positrons into a beam and accelerate them strongly.” In numbers: Over a distance of just 50 micrometers, the particles should reach an energy of one gigaelectronvolt (GeV) — a size that usually requires a full-grown particle accelerator.

Jul 23, 2021

Can consciousness be explained by quantum physics? Research is closer to finding out

Posted by in categories: computing, cosmology, neuroscience, particle physics, quantum physics

One of the most important open questions in science is how our consciousness is established. In the 1990s, long before winning the 2020 Nobel Prize in Physics for his prediction of black holes, physicist Roger Penrose teamed up with anaesthesiologist Stuart Hameroff to propose an ambitious answer.

They claimed that the brain’s neuronal system forms an intricate network and that the consciousness this produces should obey the rules of quantum mechanics —the theory that determines how tiny particles like electrons move around. This, they argue, could explain the mysterious complexity of human consciousness.

Continue reading “Can consciousness be explained by quantum physics? Research is closer to finding out” »

Jul 22, 2021

Can artificial intelligence help scientists spot gravitational waves?

Posted by in categories: cosmology, physics, robotics/AI

Scientists hunting for elusive gravitational waves across the universe may be able to supercharge their discoveries with a new tool: artificial intelligence.

Gravitational waves are ripples in spacetime, created when a massive object is accelerated or disturbed, such as when a black hole and a neutron star collide. Theorized by Albert Einstein, their existence was confirmed in 2015 with the first gravitational wave discovery by researchers using LIGO (the advanced Laser Interferometer Gravitational-Wave Observatory). Now, just six years later, there have been at least 50 gravitational wave events detected.

Jul 20, 2021

Can Consciousness Be Explained by Quantum Physics?

Posted by in categories: computing, cosmology, neuroscience, particle physics, quantum physics

One of the most important open questions in science is how our consciousness is established. In the 1990s, long before winning the 2020 Nobel Prize in Physics for his prediction of black holes, physicist Roger Penrose teamed up with anaesthesiologist Stuart Hameroff to propose an ambitious answer.

They claimed that the brain’s neuronal system forms an intricate network and that the consciousness this produces should obey the rules of quantum mechanics – the theory that determines how tiny particles like electrons move around. This, they argue, could explain the mysterious complexity of human consciousness.

Continue reading “Can Consciousness Be Explained by Quantum Physics?” »

Jul 19, 2021

Gravitational-Wave Observatories Detect Rare Mergers of Black Holes With Neutron Stars for the First Time

Posted by in categories: cosmology, physics

Salvatore Vitale describes how gravitational-wave signals suggest black holes completely devoured their companion neutron stars.

Recently, an international team of scientists, including researchers at MIT, announced the detection of a new kind of astrophysical system: a collision between a black hole and a neutron star — two of the densest, most exotic objects in the universe.

Scientists have detected signals of colliding black holes, and colliding neutron stars, but had not confirmed a merging of a black hole with a neutron star until now. In a study appearing today in The Astrophysical Journal Letters, the scientists report observing not just one, but two such rare events, each of which gave off gravitational waves that reverberated across a large swath of the universe before reaching Earth in January 2020, just 10 days apart.

Continue reading “Gravitational-Wave Observatories Detect Rare Mergers of Black Holes With Neutron Stars for the First Time” »

Jul 19, 2021

Dark Heart of the Nearest Radio Galaxy Pinpointed

Posted by in category: cosmology

An international team anchored by the Event Horizon Telescope (EHT) Collaboration, which is known for capturing the first image of a black hole in the galaxy Messier 87, has now imaged the heart of the nearby radio galaxy Centaurus A in unprecedented detail. The astronomers pinpoint the location of the central supermassive black hole and reveal how a gigantic jet is being born. Most remarkably, only the outer edges of the jet seem to emit radiation, which challenges our theoretical models of jets. This work, led by Michael Janssen from the Max Planck Institute for Radio Astronomy in Bonn and Radboud University Nijmegen is published in Nature Astronomy today (July 19th, 2021).

At radio wavelengths, Centaurus A emerges as one of the largest and brightest objects in the night sky. After it was identified as one of the first known extragalactic radio sources in 1949, Centaurus A has been studied extensively across the entire electromagnetic spectrum by a variety of radio, infrared, optical, X-ray, and gamma-ray observatories. At the center of Centaurus A lies a black hole with the mass of 55 million suns, which is right between the mass scales of the Messier 87 black hole (six and a half billion suns) and the one in the center of our own galaxy (about four million suns).

Jul 16, 2021

Massive Stellar Explosion Illuminates Thousand-Year-Old Astronomical Mystery

Posted by in categories: cosmology, quantum physics

A star in a distant galaxy blew up in a powerful explosion, solving an astronomical mystery.

Dr. Iair Arcavi, a Tel Aviv University researcher at the Raymond and Beverly Sackler Faculty of Exact Sciences, participated in a study that discovered a new type of stellar explosion — an electron-capture supernova. While they have been theorized for 40 years, real-world examples have been elusive. Such supernovas arise from the explosions of stars 8–9 times the mass of the sun. The discovery also sheds new light on the thousand-year mystery of the supernova from A.D. 1054 that was seen by ancient astronomers, before eventually becoming the Crab Nebula, that we know today.

A supernova is the explosion of a star following a sudden imbalance between two opposing forces that shaped the star throughout its life. Gravity tries to contract every star. Our sun, for example, counter balances this force through nuclear fusion in its core, which produces pressure that opposes the gravitational pull. As long as there is enough nuclear fusion, gravity will not be able to collapse the star. However, eventually, nuclear fusion will stop, just like gas runs out in a car, and the star will collapse. For stars like the sun, the collapsed core is called a white dwarf. This material in white dwarfs is so dense that quantum forces between electrons prevent further collapse.

Continue reading “Massive Stellar Explosion Illuminates Thousand-Year-Old Astronomical Mystery” »

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