Archive for the ‘physics’ category: Page 11

Dec 18, 2023

Defying Physics: “Forbidden” Emissions From a Spiral Galaxy

Posted by in categories: cosmology, physics

This whirling Hubble Space Telescope image features a bright spiral galaxy known as MCG-01–24-014, which is located about 275 million light-years from Earth. In addition to being a well-defined spiral galaxy, MCG-01–24-014 has an extremely energetic core, known as an active galactic nucleus (AGN), so it is referred to as an active galaxy.

Even more specifically, it is categorized as a Type-2 Seyfert galaxy. Seyfert galaxies host one of the most common subclasses of AGN, alongside quasars. Whilst the precise categorization of AGNs is nuanced, Seyfert galaxies tend to be relatively nearby ones where the host galaxy remains plainly detectable alongside its central AGN, while quasars are invariably very distant AGNs whose incredible luminosities outshine their host galaxies.

Dec 18, 2023

We Now Have Precise Math To Describe How Black Holes Reflect Our Universe

Posted by in categories: cosmology, information science, mathematics, physics

Astronomers developed a set of equations that can precisely describe the reflections of the Universe that appear in the warped light around a black hole.

The proximity of each reflection is dependent on the angle of observation with respect to the black hole, and the rate of the black hole’s spin, according to a mathematical solution worked out by physics student Albert Sneppen of the Niels Bohr Institute in Denmark in July 2021.

This was really cool, absolutely, but it wasn’t just really cool. It also potentially gave us a new tool for probing the gravitational environment around these extreme objects.

Dec 18, 2023

Discovery of Massive Stars Stripped of Hydrogen Envelopes in Binary Systems

Posted by in categories: physics, space

“This was such a big, glaring hole,” said Dr. Maria Drout. “If it turned out that these stars are rare, then our whole theoretical framework for all these different phenomena is wrong, with implications for supernovae, gravitational waves, and the light from distant galaxies. This finding shows these stars really do exist.”

Can binary stars steal material from each other? This is what a recent study published in Science hopes to address as a team of international researchers examined how the interaction between binary stars can cause one star to strip material from its companion star over time, resulting in one massive star and one much smaller star. While this study could help astronomers better understand precursor signs to supernovae, scientists have only identified one candidate for being stripped of its hydrogen material, despite longstanding hypotheses that one in three binary stars are stripped of their hydrogen.

Dec 18, 2023

Physics behind Unusual Behavior of Stars’ Super Flares discovered

Posted by in categories: physics, space

Our sun actively produces solar flares that can impact Earth, with the strongest flares having the capacity to cause blackouts and disrupt communications—potentially on a global scale. While solar flares can be powerful, they are insignificant compared to the thousands of “super flares” observed by NASA’s Kepler and TESS missions. “Super flares” are produced by stars that are 100–10,000 times brighter than those on the sun.

The physics are thought to be the same between solar flares and super flares: a sudden release of magnetic energy. Super-flaring stars have stronger magnetic fields and thus brighter flares but some show an unusual behavior—an initial, short-lived brightness enhancement, followed by a secondary, longer-duration but less intense flare.

A team led by University of Hawaiʻi Institute for Astronomy Postdoctoral Researcher Kai Yang and Associate Professor Xudong Sun developed a model to explain this phenomenon, which was published today in The Astrophysical Journal.

Dec 17, 2023

Physicist Discovers ‘Paradox-Free’ Time Travel Is Theoretically Possible

Posted by in categories: physics, space, time travel

No one has yet managed to travel through time – at least to our knowledge – but the question of whether or not such a feat would be theoretically possible continues to fascinate scientists.

As movies such as The Terminator, Donnie Darko, Back to the Future and many others show, moving around in time creates a lot of problems for the fundamental rules of the Universe: if you go back in time and stop your parents from meeting, for instance, how can you possibly exist in order to go back in time in the first place?

It’s a monumental head-scratcher known as the ‘grandfather paradox’, but a few years ago physics student Germain Tobar, from the University of Queensland in Australia, worked out how to “square the numbers” to make time travel viable without the paradoxes.

Dec 16, 2023

Hong Kong develops world’s first antenna for ultra-secure 6G

Posted by in categories: computing, internet, physics

Researchers call it the ‘Holy Grail’ for physicists and engineers.

A group of researchers, led by Professor Chan Chi-hou from the City University of Hong Kong, created a special antenna that can control all five important aspects of electromagnetic waves using computer software.

The antenna, which they have named ’microwave universal metasurface antenna,’ is capable of dynamically, simultaneously, independently, and precisely manipulating all the essential properties of electromagnetic waves through software control.

Continue reading “Hong Kong develops world’s first antenna for ultra-secure 6G” »

Dec 14, 2023

How do magnets work?

Posted by in category: physics

For centuries, people have been mystified by magnets and wondered how they worked. In this video, Fermilab’s Dr. Don tells us how.

How Einstein saved magnet theory:
• How Einstein saved magnet theory.

Continue reading “How do magnets work?” »

Dec 14, 2023

Newly developed material gulps down hydrogen, spits it out, protects fusion reactor walls

Posted by in categories: engineering, nuclear energy, physics

University of Wisconsin–Madison engineers have used a spray coating technology to produce a new workhorse material that can withstand the harsh conditions inside a fusion reactor.

The advance, detailed in a paper published recently in the journal Physica Scripta, could enable more efficient compact fusion reactors that are easier to repair and maintain.

“The fusion community is urgently looking for new manufacturing approaches to economically produce large plasma-facing components in fusion reactors,” says Mykola Ialovega, a postdoctoral researcher in and engineering physics at UW–Madison and lead author on the paper. “Our technology shows considerable improvements over current approaches. With this research, we are the first to demonstrate the benefits of using cold spray coating technology for fusion applications.”

Dec 14, 2023

Gravitational Waves Unveil Thermal Secrets in Neutron Star Mergers

Posted by in categories: physics, space, supercomputing

Simulations of binary neutron star mergers suggest that future detectors will distinguish between different models of hot nuclear matter.

Researchers used supercomputer simulations to explore how neutron star mergers affect gravitational waves, finding a key relationship with the remnant’s temperature. This study aids future advancements in detecting and understanding hot nuclear matter.

Exploring neutron star mergers and gravitational waves.

Dec 14, 2023

A bend in universe: Researchers may have discovered the cosmic string proof

Posted by in categories: physics, space

A recent analysis of a peculiar pair of galaxies located billions of light-years away suggests the possibility of a cosmic string —a hypothetical feature in the fabric of the Universe. Initially considered distinct, the two galaxies may be duplicated images caused by gravitational lensing, a phenomenon where space-time bends around foreground mass, acting like a lens.

Led by researchers of the Indian Institute of Astrophysics, the study identifies a cosmic string candidate, CSc-1, in the cosmic microwave background, the lingering radiation from the Universe’s birth. Cosmic strings, theoretical one-dimensional wrinkles formed at the dawn of time, are believed to be highly dense and massive, potentially extending across the entire Universe.

Observationally proving cosmic strings is challenging because their effects can resemble other phenomena. However, minute differences in their impact distinguish them. The researchers focused on a galaxy pair, SDSSJ110429, within CSc-1 as a potential cosmic string signature. Gravitational lensing typically involves a foreground mass causing observable distortions, but SDSSJ110429 lacks evident foreground mass or distorted light.

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