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Archive for the ‘cosmology’ category: Page 69

Jun 8, 2023

Quantum simulation of Hawking radiation and curved spacetime with a superconducting on-chip black hole

Posted by in categories: computing, cosmology, quantum physics

Recently, the theory of Hawking radiation of a black hole has been tested in several analogue platforms. Shi et al. report a fermionic-lattice model realization of an analogue black hole using a chain of superconducting transmon qubits with tuneable couplers and show the stimulated Hawking radiation.

Jun 8, 2023

A Huge Black-Hole just turned its whole magnetic field around

Posted by in categories: computing, cosmology, particle physics

Black holes, cosmic power stations, fuel the luminosity of quasars and active galactic nuclei (AGNs) through their intricate interaction of matter, gravity, and magnetic forces. Despite black holes themselves not possessing a magnetic field, the surrounding dense plasma in the accretion disc does. As this plasma orbits the black hole, its charged particles generate an electric current and consequently a magnetic field.

This magnetic field, assumed to be stable due to the unvarying plasma flow, caused scientists to scratch their heads when they found evidence of its directional change. Such a phenomenon, known as a magnetic reversal, is akin to an imaginary pole of a magnet switching from north to south or vice versa. While not uncommon in stars, and even witnessed in the Sun’s 11-year sunspot cycle or Earth’s infrequent magnetic shifts, such an event was thought improbable for supermassive black holes.

In 2018, a computer-aided sky survey detected a startling transformation in a galaxy 239 million light-years away named 1ES 1927+654, which had suddenly become a hundredfold brighter. Swift Observatory soon reported x-ray and ultraviolet light emissions from this region. Initial speculations suggested a tidal disruption event caused by a star venturing too close to the galaxy’s central supermassive black hole, disrupting gas flow into the accretion disc, as the reason for this unusual luminosity.

Jun 8, 2023

Galaxy Cluster MACS 1206

Posted by in categories: cosmology, mapping

This image of galaxy cluster MACS J1206.2–0847 (or MACS 1,206 for short) is part of a broad survey with NASA’s Hubble Space Telescope.

The distorted shapes in the cluster are distant galaxies from which the light is bent by the gravitational pull of an invisible material called dark matter within the cluster of galaxies. This cluster is an early target in a survey that will allow astronomers to construct the most detailed dark matter maps of more galaxy clusters than ever before.

These maps are being used to test previous, but surprising, results that suggest that dark matter is more densely packed inside clusters than some models predict. This might mean that galaxy cluster assembly began earlier than commonly thought.

Jun 7, 2023

X-ray Emissions from Black Hole Jets Vary Unexpectedly, Challenging Leading Model of Particle Acceleration

Posted by in categories: cosmology, particle physics

Researchers discovered only relatively recently that black hole jets emit X-rays, and how the jets accelerate particles to this high-energy state is still a mystery. Surprising new findings in Nature Astronomy appear to rule out one leading theory, opening the door to reimagining how particle acceleration works in the jets—and possibly also elsewhere in the universe.

One leading model of how jets generate X-rays expects the jets’ X-ray emissions to remain stable over long time scales (millions of years). However, the new paper found that the X-ray emissions of a statistically significant number of jets varied over just a few years.

“One of the reasons we’re excited about the variability is that there are two main models for how X-rays are produced in these jets, and they’re completely different,” explains lead author Eileen Meyer, an astronomer at University of Maryland, Baltimore County. “One model invokes very low-energy electrons and one has very high-energy electrons. And one of those models is completely incompatible with any kind of variability.”

Jun 7, 2023

Gemini North back on sky with dazzling image of supernova in the Pinwheel Galaxy

Posted by in categories: cosmology, physics

The Gemini North telescope, one half of the International Gemini Observatory operated by NSF’s NOIRLab, has returned from a seven-month hiatus literally with a bang, as it has captured the spectacular aftermath of a supernova, a massive star that exploded in the large, face-on, spiral Pinwheel Galaxy (Messier 101). The supernova, named SN 2023ixf (lower left), was discovered on May 19 by amateur astronomer Koichi Itagaki.

Since its discovery, observers around the globe have pointed their telescopes toward Messier 101 to get a look at the burst of light. Over the coming months, Gemini North will allow astronomers to study how the light from the fades and how its spectrum evolves over time, helping astronomers better understand the physics of such explosions.

Continue reading “Gemini North back on sky with dazzling image of supernova in the Pinwheel Galaxy” »

Jun 7, 2023

Is there an infinite universe? According to scientists, our universe has no beginning

Posted by in categories: cosmology, evolution, quantum physics, singularity

The Big Bang, traditionally considered the birth of the universe about 14 billion years ago, is being questioned. Physicist Bruno Bento and his team have proposed compelling research suggesting the universe may have always existed, and the Big Bang may merely be a significant event in its continuous evolution.

Bruno Bento and his colleagues set out to examine what the universe’s inception might have looked like without a Big Bang singularity. They grappled with contradictions arising when comparing accepted theories, particularly those dealing with quantum physics and general relativity. While quantum physics has accurately described three of the four fundamental forces of nature, it struggles to incorporate gravity. On the other hand, general relativity offers a comprehensive explanation of gravity, but falters when dealing with black holes’ centers and the universe’s genesis.

These contentious areas, termed “singularities,” are points in space-time where established physical laws cease to apply. Intriguingly, computations indicate an immense gravitational pull within singularities, even on a minuscule scale.

Jun 7, 2023

Hundreds of ancient, invisible structures discovered near our galaxy’s center

Posted by in category: cosmology

Radio astronomers have discovered hundreds of long, thin structures emanating from our galaxy’s supermassive black hole.

Jun 7, 2023

In New Paradox, Black Holes Appear to Evade Heat Death

Posted by in categories: cosmology, quantum physics

The puzzling behavior of black hole interiors has led researchers to propose a new physical law: the second law of quantum complexity.

Jun 7, 2023

Scientists believe they recently discovered a Parallel Universe

Posted by in category: cosmology

A groundbreaking revelation has the scientific community buzzing: a possible encounter with a parallel universe. Researchers suggest that signs from the universe’s furthest reaches may indicate another vastly different universe has touched ours, potentially disrupting our universe’s fabric. This interpretation could validate the multiverse theory.

Researcher Dr. Ranga-Ram Chary examined the cosmic microwave background’s noise and residual signals — the remnants of the Big Bang. He discovered several sporadic bright spots, which he speculates could be the echo of our universe colliding with another billions of years ago.

This interpretation is tentative, but aligns with some cosmological theories suggesting that interactions between alternative universes could occur. These theories propose our universe is merely one bubble among countless others. Once a universe initiates in a Big Bang-like event, it perpetually expands. This rule applies to all universes, implying periodic intersections could occur.

Continue reading “Scientists believe they recently discovered a Parallel Universe” »

Jun 6, 2023

What’s the (dark) matter with Euclid?

Posted by in category: cosmology

Euclid is ESA’s mission to shed light on dark matter and dark energy, but teams at the Agency’s mission control centre in Darmstadt, Germany, are also in the dark. A series of problems have befallen the mission in pre-launch simulations.

Currently about halfway through the Euclid simulations campaign, the key focus in the Main Control Room is the Launch and Early Orbit Phase (LEOP) and spacecraft commissioning.

These are the two most critical moments in a mission’s life; as it wakes up after the rigours of launch, makes its first manoeuvres towards its target destination and as its instruments are commissioned.

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