Archive for the ‘cosmology’ category: Page 141
Mar 4, 2023
Julian Barbour on Time, the Universe, and Reality | Closer To Truth Chats
Posted by Dan Breeden in categories: cosmology, quantum physics
Julian Barbour, physicist, talks the illusion of time, the origin of the universe, and what is reality. He also discusses his newest book, “The Janus Point: A New Theory of Time,” which makes the radical argument that the growth of order drives the passage of time — and shapes the destiny of the universe.
Read “The Janus Point”: https://www.basicbooks.com/titles/julian-barbour/the-janus-point/9780465095469/
Julian Barbour’s Website: http://www.platonia.com/
Continue reading “Julian Barbour on Time, the Universe, and Reality | Closer To Truth Chats” »
Mar 3, 2023
A black hole is quickly destroying a cloud of gas. Here’s why
Posted by Paul Battista in category: cosmology
Right now, in the center of our galaxy, an enormous black hole is stretching an object apart like it were taffy. And scientists currently have a rare view, and images, of this extreme cosmic event playing out. A thick cloud of gas and dust dubbed “X7” is rapidly approaching the supermassive black hole Sagittarius A*.
Mar 3, 2023
Where is the center of the Universe? Here, there, and everywhere
Posted by Dan Breeden in categories: cosmology, neuroscience, singularity
The Big Bang is the name we have given to the moment at which the Universe began. While the idea is well known, it is often badly misunderstood. Even people with a good grasp of science have misconceptions about it. For instance, a common question is, “Where did the Big Bang happen?” And the answer to that question is a surprising one. So, let’s dive into it and try to understand where the misunderstanding arises.
When people are told of the Big Bang, they are commonly told that “all of the mass of the universe was packed into a point with zero volume called a singularity.” The singularity then “exploded,” expanding and cooling and eventually resulting in the Universe we see today. People draw from their own experience and analogize the Big Bang with something like a firecracker or a grenade — an object that sits in a location, then explodes, dispersing debris into existing space. This is a completely natural and reasonable mental image. It is also completely wrong.
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Mar 3, 2023
Major collaboration reveals new insights on binary star systems
Posted by Saúl Morales Rodriguéz in category: cosmology
Researchers from the University of Oxford have contributed to a major international study which has captured a rare and fascinating space phenomenon: binary star systems. The study, “A shared accretion instability for black holes and neutron stars,” has been published in Nature.
Scientists have long been intrigued by X-ray binary star systems, where two stars orbit around each other with one of the two stars being either a black hole or a neutron star. Both black holes and neutron stars are created in supernova explosions and are very dense—giving them a massive gravitational pull. This makes them capable of capturing the outer layers of the normal star that orbits around it in the binary system, seen as a rotating disk of matter (mimicking a whirlpool) around the black hole/neutron star.
According to theoretical calculations, these rotating disks should show a dynamic instability: about once an hour, the inner parts of the disk rapidly fall onto the black hole/neutron star, after which these inner regions re-fill and the process repeats. Up to now, this violent and extreme process had only been directly observed once, in a black hole binary system. For the first time, it has now been seen in a neutron star binary system, called Swift J1858.6–0814. This discovery demonstrates that this instability is a general property of these disks (and not caused by the presence of a black hole).
Mar 2, 2023
Black Holes Are Even Weirder Than You Thought!
Posted by Dan Breeden in categories: cosmology, information science, mathematics, singularity
Claim your SPECIAL OFFER for MagellanTV here: https://try.magellantv.com/arvinash Start your free trial TODAY so you can watch The Most Powerful Black Holes in the Universe” about the extremes of time and space, and the rest of MagellanTV’s science collection: https://www.magellantv.com/watch/the-most-powerful-black-hol…niverse-4k.
REFERENCES
The Tempest by Peter Cawdron: https://tinyurl.com/2ep4uzvs.
Inside Black Holes: https://youtu.be/iUr8Obv_DeA
How Black Holes form: https://youtu.be/7xCgnMqIgPI
How Stable orbits form around Black Holes: https://tinyurl.com/2klz9mfd.
Continue reading “Black Holes Are Even Weirder Than You Thought!” »
Mar 1, 2023
NASA sheds light on a massive supernova dating back to Middle Ages
Posted by Gemechu Taye in categories: cosmology, particle physics
The supernova is so old that it is believed to have been described in a passage of Shakespeare’s “Hamlet.”
A group of scientists has shed new light on a star that exploded in a supernova more than 450 years ago, blasting particles out into space at close to the speed of light.
Now, astronomers have used NASA’s Imaging X-ray Polarimetry to study the incredibly long-lasting aftereffects of the supernova called Tycho.
Continue reading “NASA sheds light on a massive supernova dating back to Middle Ages” »
Mar 1, 2023
A “runaway” supermassive black hole is hurtling through the universe at an astonishing speed
Posted by Paul Battista in category: cosmology
For the last 50 years, astronomers have speculated that some supermassive black holes might “run away” from their home galaxies given the right conditions. Now, astronomers believe they have discovered a strong candidate for a supermassive black hole that has done just that, according to new research published on the preprint server arXiv.org, which has been accepted for publication in The Astrophysical Journal.
One of the great questions for humanity is whether we are alone in the universe. Indeed, astrobiologists appear tantalizingly close to being able to spot the signs of life on other Earths — should it exist elsewhere — using modern observatories such as the James Webb Space Telescope.
Now a group of astronomers have taken this question further by asking whether life could exist in other universes. In other words, they want to know whether we are alone in the multiverse. And they have developed a way to explore this question by considering the range of conditions that might exist in other universes.
The question comes about because the fundamental constants that govern physical laws have values that seem perfectly arranged to allow life to emerge.
Feb 28, 2023
If these points are galaxies, they’ll rewrite cosmic history
Posted by Atanas Atanasov in category: cosmology
New galaxy candidates from a James Webb Space Telescope survey have astronomers shocked and thrilled.
New results show fully formed galaxies in the early Universe that could rewrite what we know about galaxies and black holes.