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Archive for the ‘cosmology’ category: Page 208

Apr 10, 2022

Dark matter could be a cosmic relic from extra dimensions

Posted by in categories: cosmology, particle physics

But these particles would interact only weakly with ordinary matter, and only via the force of gravity. This description is eerily similar to what we know about dark matter, which does not interact with light yet has a gravitational influence felt everywhere in the universe. This gravitational influence, for instance, is what prevents galaxies from flying apart.

“The main advantage of massive gravitons as dark matter particles is that they only interact gravitationally, hence they can escape attempts to detect their presence,” Cacciapaglia said.

In contrast, other proposed dark matter candidates — such as weakly interacting massive particles, axions and neutrinos — might also be felt by their very subtle interactions with other forces and fields.

Apr 10, 2022

Hubble captures spiral galaxy in constellation of Serpens

Posted by in category: cosmology

The image from the Hubble Space Telescope shared this week shows a “serpentine” galaxy with winding, snake-like spiral arms, and is appropriately enough located in the constellation of Serpens, or The Snake. Technically known as NGC 5,921, the galaxy is located 80 million light-years away.

The galaxy NGC 5,921 is a type called a barred spiral galaxy, like our Milky Way. The bar refers to the strip of bright light across the center of the galaxy, which is a region of dust and gas where many stars are born — hence why it glows brightly. Around half of known galaxies have bars, and researchers think that they develop as galaxies get older and dust and gas are drawn in toward their center by gravity.

The image was taken as part of a Hubble study into how the supermassive black holes at the hearts of galaxies relate to the stars within them. Hubble used its Wide Field Camera 3 instrument to take the image, which was combined with data from the ground-based Gemini Observatory.

Apr 9, 2022

Fermilab Says Particle Is Heavy Enough to Break the Standard Model

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

If the W’s excess heft relative to the standard theoretical prediction can be independently confirmed, the finding would imply the existence of undiscovered particles or forces and would bring about the first major rewriting of the laws of quantum physics in half a century.

“This would be a complete change in how we see the world,” potentially even rivaling the 2012 discovery of the Higgs boson in significance, said Sven Heinemeyer, a physicist at the Institute for Theoretical Physics in Madrid who is not part of CDF. “The Higgs fit well into the previously known picture. This one would be a completely new area to be entered.”

The finding comes at a time when the physics community hungers for flaws in the Standard Model of particle physics, the long-reigning set of equations capturing all known particles and forces. The Standard Model is known to be incomplete, leaving various grand mysteries unsolved, such as the nature of dark matter. The CDF collaboration’s strong track record makes their new result a credible threat to the Standard Model.

Apr 9, 2022

We can build a real, traversable wormhole … if the universe has extra dimensions

Posted by in categories: cosmology, physics

We can build a real, traversable wormhole… if the universe has extra dimensions.


It may be possible to build a real, traversable wormhole, but only if our universe has extra dimensions, a team of physicists has found.

Apr 8, 2022

New data on an elusive particle could upend physics as we know it

Posted by in categories: cosmology, particle physics

The W boson measurement provides insight into the weak nuclear force, and could explain other longstanding mysteries like antimatter imbalance and dark matter.

Apr 7, 2022

Massive Black Holes Shown to Act Like Quantum Particles

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

Physicists are using quantum math to understand what happens when black holes collide. In a surprise, they’ve shown that a single particle can describe a collision’s entire gravitational wave.

Apr 7, 2022

LHCb reveals secret of antimatter creation in cosmic collisions

Posted by in categories: cosmology, particle physics

At the Quark Matter conference today and at the recent Rencontres de Moriond conference, the LHCb collaboration presented an analysis of particle collisions at the Large Hadron Collider (LHC) that may help determine whether or not any antimatter seen by experiments in space originates from the dark matter that holds galaxies such as the Milky Way together.

Space-based experiments such as the Alpha Magnetic Spectrometer (AMS), which was assembled at CERN and is installed on the International Space Station, have detected the fraction of antiprotons, the antimatter counterparts of protons, in high-energy particles called cosmic rays. These antiprotons could be created when dark-matter particles collide with each other, but they could also be formed in other instances, such as when protons collide with atomic nuclei in the interstellar medium, which is mainly made up of hydrogen and helium.

To find out whether or not any of these antiprotons originate from dark matter, physicists therefore have to estimate how often antiprotons are produced in collisions between protons and hydrogen as well as between protons and helium. While some measurements of the first have been made, and LHCb reported in 2017 the first-ever measurement of the second, that LHCb measurement involved only prompt antiproton production – that is, antiprotons produced right at the place where the collisions took place.

Apr 7, 2022

Astronomers have found what may be the most distant galaxy ever seen

Posted by in category: cosmology

A galaxy called HD1 may be the most distant object astronomers have ever spotted. Its astonishing brightness is difficult to explain and may be due to an enormous black hole at its centre or the creation of extremely massive primordial stars, both of which confound our understanding of the early universe.

Fabio Pacucci at the Harvard-Smithsonian Center for Astrophysics in Massachusetts and his colleagues found HD1 by sifting through large public data sets from several of the most powerful telescopes available. They then observed it again with the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile.

Those observations showed that HD1 is about 33.4 billion light years away, more than a billion light years further than the previous most distant object ever spotted, a galaxy called GN-z11. Such a distance is possible, despite the age of the universe being only about 13.8 billion years, because of the accelerating expansion of the cosmos.

Apr 7, 2022

Man photographs ISS from Earth’s surface, captures astronauts in space

Posted by in category: cosmology

A German astrophotographer has taken an HD photo of the ISS from the surface of Earth, showing two astronauts on a spacewalk.

Apr 7, 2022

Hubble views a galaxy with an active black hole

Posted by in category: cosmology

This image from the NASA/ESA Hubble Space Telescope reveals tendrils of dark dust threading across the heart of the spiral galaxy NGC 7172. The galaxy lies approximately 110 million light-years from Earth in the constellation Piscis Austrinus. The lane of dust threading its way across NGC 7,172 is obscuring the luminous heart of the galaxy, making NGC 7,172 appear to be nothing more than a normal spiral galaxy viewed from the side.

When astronomers inspected NGC 7,172 across the they quickly discovered that there was more to it than meets the eye: NGC 7,172 is a Seyfert galaxy—a type of galaxy with an intensely luminous active galactic nucleus powered by matter accreting onto a supermassive black hole.

This image combines data from two sets of Hubble observations, both proposed to study nearby . The image also combines data from two instruments—Hubble’s Advanced Camera for Surveys and Wide Field Camera 3.