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Archive for the ‘cosmology’ category: Page 64

Mar 15, 2024

Do black holes explode? The 50-year-old puzzle that challenges quantum physics

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

In hindsight, it seems prophetic that the title of a Nature paper published on 1 March 1974 ended with a question mark: “Black hole explosions?” Stephen Hawking’s landmark idea about what is now known as Hawking radiation1 has just turned 50. The more physicists have tried to test his theory over the past half-century, the more questions have been raised — with profound consequences for how we view the workings of reality.

In essence, what Hawking, who died six years ago today, found is that black holes should not be truly black, because they constantly radiate a tiny amount of heat. That conclusion came from basic principles of quantum physics, which imply that even empty space is a far-from-uneventful place. Instead, space is filled with roiling quantum fields in which pairs of ‘virtual’ particles incessantly pop out of nowhere and, under normal conditions, annihilate each other almost instantaneously.

However, at an event horizon, the spherical surface that defines the boundary of a black hole, something different happens. An event horizon represents a gravitational point of no return that can be crossed only inward, and Hawking realized that there two virtual particles can become separated. One of them falls into the black hole, while the other radiates away, carrying some of the energy with it. As a result, the black hole loses a tiny bit of mass and shrinks — and shines.

Mar 13, 2024

Deciphering the Dark: The Accelerating Universe and the Quest for Dark Energy

Posted by in categories: cosmology, physics

Dark energy’s role in propelling the universe’s accelerated expansion presents a pivotal challenge in astrophysics, driving ongoing research and space missions dedicated to uncovering the nature of this mysterious force.

Some 13.8 billion years ago, the universe began with a rapid expansion we call the Big Bang. After this initial expansion, which lasted a fraction of a second, gravity started to slow the universe down. But the cosmos wouldn’t stay this way. Nine billion years after the universe began, its expansion started to speed up, driven by an unknown force that scientists have named dark energy.

But what exactly is dark energy?

Mar 12, 2024

JWST Unveils the Earliest Galaxy Merger: Insights into Rapid Star Formation

Posted by in categories: cosmology, evolution

How fast did the first galaxies and stars form after the Big Bang? This is what a recent study published in Nature Astronomy hopes to address as an international team of scientists led by the University of Melbourne used NASA’s James Webb Space Telescope (JWST) to observe the merger of two galaxies that occurred approximately 510 million years after the Big Bang, or approximately 13 billion years ago. This study holds the potential to help astronomers better understand the processes behind galaxy formation and evolution during the universe’s youth.

“It is amazing to see the power of JWST to provide a detailed view of galaxies at the edge of the observable Universe and therefore back in time” said Dr. Michele Trenti, who is a Professor and Cosmologist in the School of Physics at the University of Melbourne and a co-author on the study. “This space observatory is transforming our understanding of early galaxy formation.”

For the study, the researchers used JWST’s powerful infrared instruments to observe what they hypothesize to be two merging galaxies comprised of a primary clump and a long tail with a mass equivalent to approximately 1.6 × 109 masses of our Sun that contains approximately 10 percent of the metals of our Sun and growing by approximately 19 solar masses per year. Additionally, they estimate the stars within these merging galaxies are less than 10 million years old within the main clump of the merger and stars in the outer regions to be approximately 120 million years old.

Mar 11, 2024

The Indian Ocean Has the World’s Largest Gravity ‘Black Hole’ and It’s Finally Explained

Posted by in category: cosmology

Due to the world’s largest gravity hole, the sea level in a large part of the Indian Ocean is up to 106 m (348 ft) lower than the rest of the world. We have just understood what causes this huge ‘black hole.’

If you look at a map of Earth’s gravity, you will see a huge blue spot south of India, indicating a region where gravity is weaker than average. This spot is called the Indian Ocean Geoid Low (IOGL), and it is the largest gravity anomaly on our planet.

A gravity anomaly is a difference between the actual gravity measured at a location and the theoretical gravity expected for a perfectly smooth and spherical Earth. But Earth’s gravity isn’t perfectly uniform and variations in mass distribution beneath the surface cause fluctuations in gravitational pull.

Mar 10, 2024

Scientists detect ultralow gravitational waves in pulsar data

Posted by in categories: cosmology, physics

Physicists debut a new method to detect gravitational waves with unprecedented precision, providing insights into black hole mergers.

Mar 10, 2024

Fresh X-Rays Reveal a Universe as Clumpy as Cosmology Predicts

Posted by in categories: cosmology, mapping

A recent study of thousands of galaxy clusters may ease a debate about the clumpiness of cosmic matter and reinforce the standard model of cosmology.


By mapping the largest structures in the universe in X-rays, cosmologists have found striking agreement with their standard theoretical model of how the universe evolves.

Mar 10, 2024

Unlocking the Secrets Behind Galaxy Formation

Posted by in categories: cosmology, space travel, supercomputing

Astronomers can use supercomputers to simulate the formation of galaxies from the Big Bang 13.8 billion years ago to the present day. But there are a number of sources of error. An international research team, led by researchers in Lund, has spent a hundred million computer hours over eight years trying to correct these.

The last decade has seen major advances in computer simulations that can realistically calculate how galaxies form. These cosmological simulations are crucial to our understanding of where galaxies, stars, and planets come from. However, the predictions from such models are affected by limitations in the resolution of the simulations, as well as assumptions about a number of factors, such as how stars live and die and the evolution of the interstellar medium.

Collaborative Efforts Enhance Accuracy

Mar 9, 2024

Webb Telescope Discovers Ancient ‘Dead’ Galaxy: A Look Back 13 Billion Years

Posted by in categories: cosmology, evolution

“The first few hundred million years of the universe was a very active phase, with lots of gas clouds collapsing to form new stars,” said Dr. Tobias Looser.


When do galaxies stop forming new stars? This is what a study published today in Nature hopes to address as a team of researchers led by the Kavli Institute for Cosmology used NASA’s James Webb Space Telescope (JWST) to discover a 13-billion-year-old “dead” galaxy that stopped producing stars shortly after its own formation, approximately 700 million years after the Big Bang. This study holds the potential to help astronomers better understand the formation and evolution of galaxies in the early universe and the processes behind why some of these galaxies cease to form new stars.

For the study, the researchers used JWST’s powerful Near Infrared Spectrograph (NIRSpec) instrument as part of the JWST Advanced Deep Extragalactic Survey (JADES) to observe the earliest galaxies that existed approximately 700 million years after the Big Bang, or approximately 13 billion years old. Through this, the team observed what they referred to as a “dead” galaxy, meaning a galaxy that ceased producing new stars, which is a profound discovery considering the young age of the universe at the time. But the question is how did this happen?

Continue reading “Webb Telescope Discovers Ancient ‘Dead’ Galaxy: A Look Back 13 Billion Years” »

Mar 9, 2024

Multiverse raises $27M for quantum software targeting LLM leviathans

Posted by in categories: business, cosmology, finance, quantum physics, robotics/AI

We’re still years away from seeing physical quantum computers break into the market with any scale and reliability, but don’t give up on deep tech just yet. The market for high-level quantum computer science — which applies quantum principles to manage complex computations in areas like finance and artificial intelligence — appears to be quickening its pace.

In the latest development, a startup out of San Sebastian, Spain, called Multiverse Computing has raised €25 million (or $27 million) in an equity funding round led by Columbus Venture Partners. The funding values the startup at €100 million ($108 million), and it will be used in two main areas. The startup plans to continue building out its existing business working with startups in verticals like manufacturing and finance, and it wants to forge new efforts to work more closely with AI companies building and operating large language models.

In both cases, the pitch is the same, said CEO Enrique Lizaso Olmos: “optimization.”

Mar 9, 2024

Study shows that the ATLAS detector can measure the flux of high-energy supernova neutrinos

Posted by in categories: cosmology, particle physics

High-energy neutrinos are extremely rare particles that have so far proved very difficult to detect. Fluxes of these rare particles were first detected by the IceCube Collaboration back in 2013.

Recent papers featured in Physical Review D and The Astrophysical Journal Letters found that nearby supernovae, especially Galactic ones, would be promising sources of high-energy neutrinos. This has inspired new studies exploring the possibility of detecting neutrinos originating from these sources using large particle collider detectors, such as the ATLAS detector at CERN.

Researchers at Harvard University, University of Nevada and Pennsylvania State University recently demonstrated that the ATLAS detector can measure the flux of high-energy supernova neutrinos. Their new paper, published in Physical Review Letters, could inspire future efforts aimed at detecting fluxes of high-energy neutrinos.

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