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Archive for the ‘cosmology’ category: Page 113

Jul 19, 2023

PandaX sets new constraints on the search for light dark matter via ionization signals

Posted by in categories: cosmology, particle physics

Teams of physicists worldwide have been trying to detect dark matter, an elusive type of matter that does not emit, absorb, or reflect light. Due to its lack of interactions with electromagnetic forces, this matter is very difficult to observe directly, thus most researchers are instead searching for signals originating from its interactions with other particles in its surroundings.

The PandaX experiment is a research effort dedicated to the search of dark matter using data collected by the Particle and Astrophysical xenon detector, situated at the China Jinping Underground Laboratory (CJPL) in Sichuan, in China. In a recent paper published in Physical Review Letters, the researchers involved in this large-scale experiment published the results of their most recent search for light dark matter (i.e., weakly interacting massive particles with masses below 1 GeV).

“Currently, strong constraints exist for heavy mass derived from null results in direct detection experiments using xenon detectors,” Yue Meng, Qing Lin and Ning Zhou told Tech Xplore, on behalf of the PandaX collaboration. “However, traditional searches are not sensitive to light mass dark matter (less than GeV/c2) due to the detection energy threshold. Using an ionization-only signal (S2-only) to search for light mass dark matter can reduce the energy threshold from ~1 keV to 0.1 keV. Previous S2-only data analyses in xenon detectors were unable to model the background, which prevented effective and sensitive searches for light mass dark matter.”

Jul 19, 2023

Researchers operating Gamma-ray Burst Monitor discover brightest gamma-ray burst ever detected

Posted by in category: cosmology

The University of Alabama in Huntsville (UAH) has announced that three researchers associated with the UAH Center for Space Plasma and Aeronomic Research (CSPAR) have discovered a gamma-ray burst (GRB) approximately 2.4 billion light-years away in the constellation Sagitta that ranks as the brightest ever observed. Believed to have been triggered by collapse of a massive star, it is accompanied by a supernova explosion, giving birth to a black hole.

Dr. Peter Veres, an assistant professor with CSPAR, Dr. Michael S. Briggs, CSPAR principal research scientist and assistant director, and Stephen Lesage, a UAH graduate research assistant, collaborated on the discovery and analysis of the . The researchers operate the Gamma-ray Burst Monitor (GBM) at UAH, a part of the University of Alabama System.

The GBM is an instrument in low-Earth orbit aboard the Fermi Gamma-ray Space Telescope that can see the entire sky not blocked by the Earth and hunts for GRBs as part of its main program.

Jul 19, 2023

Scientists Have Determined How to Travel Back in Time With a Ring Wormhole

Posted by in categories: cosmology, time travel

Scientists claim they’ve calculated a potential new method of time travel involving a theoretical object called a ring wormhole.’ Here are the details.

Jul 16, 2023

WEBB telescope finds 13 billion year-old active black hole

Posted by in category: cosmology

The James Webb Space Telescope has delivered yet another astounding discovery, spying an active supermassive black hole deeper into the universe than has ever been recorded.

The black hole lies within CEERS 1,019 — an extremely old galaxy likely formed 570 million years after the big bang — making it more than 13 billion years old. And scientists were perplexed to find just how small the celestial object’s central black hole measures.

“This black hole clocks in at about 9 million solar masses,” according to a NASA news release. A solar mass is a unit equivalent to the mass of the sun in our home solar system — which is about 333,000 times larger than the Earth.

Jul 16, 2023

Webb telescope spies most distant supermassive black hole ever recorded

Posted by in category: cosmology

The James Webb Space Telescope has delivered yet another astounding discovery, spying an active supermassive black hole deeper into the universe than has ever been recorded.

The black hole lies within CEERS 1,019 — an extremely old galaxy likely formed 570 million years after the big bang — making it more than 13 billion years old. And scientists were perplexed to find just how small the celestial object’s central black hole measures.

“This black hole clocks in at about 9 million solar masses,” according to a NASA news release. A solar mass is a unit equivalent to the mass of the sun in our home solar system — which is about 333,000 times larger than the Earth.

Jul 16, 2023

Revealing the invisible: Detecting variations in extragalactic magnetic fields

Posted by in categories: cosmology, evolution, particle physics

Magnetic fields are common throughout the universe but incredibly challenging to study. They don’t directly emit or reflect light, and light from all along the electromagnetic spectrum remains the primary purveyor of astrophysical data. Instead, researchers have had to find the equivalent of cosmic iron filings—matter in galaxies that is sensitive to magnetic fields and also emits light marked by the fields’ structure and intensity.

In a new study published in The Astrophysical Journal, several Stanford astrophysicists have studied infrared signals from just such a material—magnetically aligned dust grains embedded in the cold, dense clouds of star-forming regions. A comparison to light from cosmic ray electrons that has been marked by magnetic fields in warmer, more diffuse material showed surprising differences in the measured magnetic fields of .

Stanford astrophysicist and member of the Kavli Institute for Particle Acceleration and Cosmology (KIPAC) Enrique Lopez-Rodriguez explains the differences and what they could mean for galactic growth and evolution.

Jul 15, 2023

Physicists Just Figured Out How Wormholes Could Enable Time Travel

Posted by in categories: cosmology, education, particle physics, quantum physics, time travel

Theoretical physicists have a lot in common with lawyers. Both spend a lot of time looking for loopholes and inconsistencies in the rules that might be exploited somehow.

Valeri P. Frolov and Andrei Zelnikov from the University of Alberta in Canada and Pavel Krtouš from Charles University in Prague probably couldn’t get you out of a traffic fine, but they may have uncovered enough wiggle room in the laws of physics to send you back in time to make sure you didn’t speed through that school zone in the first place.

Shortcuts through spacetime known as wormholes aren’t recognized features of the cosmos. But for the better part of a century, scientists have wondered if the weft and warp instructed by relativity prescribe ways for quantum ripples – or even entire particles – to break free of their locality.

Jul 15, 2023

Black Holes, Dark Matter & Quantum Gravity, what’s new in Loop Quantum Gravity

Posted by in categories: cosmology, entertainment, quantum physics

Are back holes related to dark matter? Do the observations of black holes by LIGO hint at a signature of quantum gravity? Can we find evidence of black holes from a previous universe?

In 2019 second place in the Buchalter Cosmology Prize was awarded to two of the speakers you will see in this film which explores some of the above themes. We filmed this at the Loop Quantum Gravity Conference in 2019 and plan to make a follow up film exploring the latest ideas in the field.

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Jul 15, 2023

Shining Light on Cosmic Secrets: Scientists Test a Controversial Theory of Blazar Emissions

Posted by in category: cosmology

Penn State researchers have recently characterized over a hundred blazars – far-off, dynamic galaxies hosting a central supermassive black hole.

A black hole is a place in space where the gravitational field is so strong that not even light can escape it. Astronomers classify black holes into three categories by size: miniature, stellar, and supermassive black holes. Miniature black holes could have a mass smaller than our Sun and supermassive black holes could have a mass equivalent to billions of our Sun.

Jul 15, 2023

Physicists & Philosophers critique The Fine Tuning Argument

Posted by in categories: cosmology, entertainment, neuroscience, physics

The Fine-Tuning Argument is often seen as the best argument for the existence of God. Here we have assembled some of the world’s top physicists and philosophers to offer a reply. Not every critic of the argument comes from the same perspective. Some doubt there is a problem to be solved whilst others agree it is a genuine problem but think there are better solutions than the God hypothesis. Some like the multiverse and anthropics other don’t. We have tried to represent these different approaches and so it should be taken as given, that not all of the talking heads agree with each other. Nevertheless, they all share the view that the fine-tuning argument for God does not work. Nor are all the objectors atheist, Hans Halvorson offers what we think is a strong theological objection to the argument. This film does not try to argue that God doesn’t exist only that the fine-tuning argument is not a good reason to believe in God. Most of the footage was filmed exclusively for this film with some clips being re-used from our Before the Big Bang series, which can be viewed here: https://www.youtube.com/watch?v=Ry_pILPr7B8&list=PLJ4zAUPI-q…4hnojoCR4m All of the critics of the fine tuning argument that appear were sent a draft of the film more than a month before release and asked for any objections either to their appearance, the narration or any other aspect of the film. No objections were raised, and many replies were extremely positive and encouraging. A timeline of the subjects covered is below:
(We define God as a perfect Omni immaterial mind as for example modern Christians and Muslims advocate, there are other conceptions of God which our video does not address).
Just to be clear, this is a polemical film arguing against the fine tuning argument.

Continue reading “Physicists & Philosophers critique The Fine Tuning Argument” »