The crisis in Cosmology--Solved?

[caltrek]

I watch a lot of How the Universe Works on the Science Channel. One theme that comes up is a puzzle as to how supermassive black holes could have formed so early in the universe and come to be so large. Here is an article relevant to that cosmological question.

Bright But Obscured Supermassive Early Universe Black Hole Could Represent New Type
by Stephen Luntz
February 24, 2023

Introduction:

(IFL Science) The further we peer back toward the Big Bang, the more our theories run into trouble with observations. This is happening a lot right now with JWST, but ground-based telescopes are getting in on the act, including the discovery of a galaxy named COS-87259, found through the COSMOS search and confirmed by the Atacama Large Millimeter Array (ALMA). We’re seeing COS-87259 as it was just 750 million years after the universe burst into action – about 5 percent of its current age.

One notable feature of COS-87259 is its astonishing rate of star formation, a thousand times that of the Milky Way.

The light of so many hot young stars allows us to see COS-87259 despite its immense distance, but another source of luminosity is the large and growing supermassive black hole at its core, estimated to be as massive as 1.6 billion Suns. It is this that is the focus of a paper in the Monthly Notices of the Royal Astronomical Society. The authors think COS-87259’s active galactic nucleus could be key to understanding the evolution of the immensely massive black hole at the heart of most galaxies.

Supermassive black holes from the early universe have been seen for decades – indeed for a long time, they were the only thing we could see that far back. Known as quasars, they are black holes that are actively feeding on surrounding material and producing jets largely unhidden by dust. This combination makes them visible over immense distances, yet even quasars are seldom found at distances as great as COS-87259. We only average one discovery for 3,000 square degrees.

COS-87259, on the other hand, is very obscured by dust (about 2 billion solar masses of it) and consequently wouldn’t have been detectable with most prior sky surveys. Consequently, the interesting thing to astronomers is how quickly we found it once we had the capacity. The COSMOS search only studied an area of about 1.5 deg2, seven times the apparent size of the full Moon, and turned up COS-87259. Either objects like this are actually quite common – at least compared to quasars at the same distance – or astronomers got exceptionally lucky in their choice of where to look first.

Read more here: https://www.iflscience.com/bright-but- ... ype-67692

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Astronomers Present Map of Dark Matter Since Big Bang
by Candace Cheung
April 11, 2023

Introduction:

(Courthouse News) — For thousands of years, astronomers have attempted to understand the construction of the cosmos and how it has evolved into the universe we know today. A large part of research into the universe has focused on documenting mysterious dark matter and how its presence, despite our difficulties detecting it, has shaped the universe from the time of the Big Bang.

An international team of researchers have rendered new observations from the Atacama Cosmology Telescope into the most detailed map to date of dark matter across a quarter of the universe, indicating the shape and expansion rate of the universe since its creation.

Although dark matter is theorized to make up around 85% of the universe, it is usually invisible to astronomers, as it does not interact with light or electromagnetic radiation. Instead, dark matter only seems to interact with gravity, an interaction that Atacama telescope researchers took advantage of to create their map.

Presented Tuesday at “Future Science with CMB x LSS”, a conference at the Yukawa Institute for Theoretical Physics at Kyoto University in Japan, this new map depicts the usually invisible dark matter by measuring how diffuse light known as cosmic microwave background radiation warps around dark matter in a way that also confirms Albert Einstein’s theory of general relativity.

“We have mapped the invisible dark matter across the sky to the largest distances, and clearly see features of this invisible world that are hundreds of millions of light-years across," University of Cambridge cosmology professor Blake Sherwin said in a statement.

Read more here: https://www.courthousenews.com/astrono ... ig-bang/

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Scientists Get Closer to Detecting “Cosmic Dawn”
by Shirley Cardenas
April 13 , 2023

Introduction:

(Futurity) A team of scientists has doubled the sensitivity of a radio telescope called the Hydrogen Epoch of Reionization Array (HERA). With this breakthrough, they hope to peer into the secrets of the early universe.

“Over the last couple of decades, teams from around the world have worked towards a first detection of radio waves from the cosmic dawn. While such a detection remains elusive, HERA’s results represent the most precise pursuit to date,” says Adrian Liu, an assistant professor at the physics department and the Trottier Space Institute at McGill University.

650 MILLION YEARS AFTER THE BIG BANG

The array was already the most sensitive radio telescope in the world dedicated to exploring the cosmic dawn. Now the HERA team has improved its sensitivity by a factor of 2.1 for radio waves emitted about 650 million years after the Big Bang and 2.6 for radio waves emitted about 450 million years after the Big Bang.

The work appears in The Astrophysical Journal.

Although the scientists have yet to detect radio emissions from the end of the cosmic dark ages, their results provide clues about the composition of stars and galaxies in the early universe.

Read more of the Futurity article here: https://www.futurity.org/cosmic-dawn-space-2904882-2/

A highly technical presentation that appears in The Astrophysical Journal can be found here: https://iopscience.iop.org/article/10. ... 57/acaf50

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Signs of a Critical Imbalance in Physics Seen in The Arrangements of Galaxies
by Tessa Koumoundouros
May 31 , 2023

Introduction:

(Science Alert) Physicists have long puzzled over why there is more matter in the Universe than its flipped twin, antimatter. Without this imbalance, the two types of material would have canceled out, leaving nothing but a boring glow in the vast emptiness of space.

Somehow, at some point, something changed in the way the Universe works on a fundamental level, favoring the mirrored state – or parity – of one kind of 'stuff' over the other.

Scientists have sought clues to this critical moment in the remnants of the Big Bang, including the cosmic microwave background and gravitational waves, without much luck.

A study by a trio of astrophysicists from the University of Florida and the Lawrence Berkeley National Laboratory in the US has now found either a startlingly clear signal of such asymmetry soon after time began, or an absurdly specific random error.

What's more, their findings could settle the debate over whether the Universe went through a period of inflation soon after it precipitated into existence.

Read more here: https://www.sciencealert.com/signs-of- ... galaxies

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New Research Reveals Age of Universe Estimated to be 26.7 Billion Years Old
July 17, 2023

Introduction:

(Open Access Government) Challenging the current cosmological model, a new study published in the Monthly Notices of the Royal Astronomical Society suggests that the age of universe may be nearly twice as old.

This research around studying space and our universe sheds light on the “impossible early galaxy problem.”

Age of the universe estimated at 26.7 billion years

According to the study’s author, Rajendra Gupta, a physics professor at the University of Ottawa, their newly-devised model indicates that the universe is 26.7 billion years old, significantly older than the previous estimate of 13.7 billion years.

The mystery of early galaxies and methuselah stars

Astronomers and physicists have traditionally determined the universe’s age by measuring the time since the Big Bang and studying the oldest stars based on redshift observations.

Additional extract:

To address these challenges, Gupta introduces Zwicky’s tired light theory, which proposes that the redshift of light from distant galaxies is caused by the gradual energy loss of photons over vast cosmic distances.

Read more here: https://www.openaccessgovernment.org/a ... 163845/

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Cosmic Structure Growth Isn’t as Predicted
by Morgan Sherburne
September 21, 2023

Introduction:

(Futurity) The rate at which large cosmic structures grow is slower than Einstein’s Theory of General Relativity predicts, report researchers.
They also show that as dark energy accelerates the universe’s global expansion, the suppression of the cosmic structure growth that the researchers see in their data is even more prominent than what the theory predicts. Their results appear in Physical Review Letters.

As the universe evolves, scientists expect large cosmic structures to grow at a certain rate: dense regions such as galaxy clusters would grow denser, while the void of space would grow emptier.

Galaxies are threaded throughout our universe like a giant cosmic spider web. Their distribution is not random. Instead, they tend to cluster together. In fact, the whole cosmic web started out as tiny clumps of matter in the early universe, which gradually grew into individual galaxies, and eventually galaxy clusters and filaments.

“Throughout the cosmic time, an initially small clump of mass attracts and accumulates more and more matter from its local region through gravitational interaction. As the region becomes denser and denser, it eventually collapses under its own gravity,” says Minh Nguyen, lead author of the study and postdoctoral research fellow in the University of Michigan department of physics.

Read more here: https://www.futurity.org/cosmic-struct ... 77952-2/

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Largest Ever Computer Simulation of the Universe
by Govert Schilling
October 24, 2023
Introduction:

(Sky & Telescope) The Flamingo simulations are not only the largest but also the most all-encompassing simulations of the universe, from 13.75 billion years ago to today.

Using one of the most powerful supercomputers in the world, astronomers have carried out the largest ever cosmological simulations. Known as Flamingo, the simulations trace the growth of the large-scale structure of the universe over 13.75 billion years. By comparing the simulations to actual observations, scientists hope to learn about the fundamental properties of the universe that govern its long-term behavior.

Shortly after the Big Bang, the universe was filled with an almost homogeneous soup made of atoms (mostly hydrogen and helium), dark matter particles, and almost massless neutrinos. Although the average matter density was decreasing over time as space expanded, dark matter nevertheless started to clump together under its own gravity. Atoms followed suit, eventually resulting in what we observe today: a “cosmic web” of clusters and superclusters of galaxies, each galaxy containing billions of nebulae, stars, and planets.

Ever since the 1980s, astronomers have tried to reproduce this process in computer simulations. Thanks to rapid developments in computer technology, these simulations have become ever more detailed, both in size (how much space is being simulated) and in resolution (how many particles, or “elements,” are being followed). Flamingo (a convoluted acronym of Full-hydro Large-scale structure simulations with All-sky Mapping for the Interpretation of Next Generation Observations) is the largest and most complex project so far.

Conclusion:

In other words: the new Flamingo simulations might indicate that something is wrong with our cherished standard model of cosmology.

Read more of the Sky & Telescope article here: https://skyandtelescope.org/astronomy- ... iverse/

For a technical description of Flamingo: https://flamingo.strw.leidenuniv.nl

For a technical presentation of results of the Flamingo simulations as presented in Oxford Academic: https://academic.oup.com/mnras/article ... gin=false

[raklian]

Interesting hypothesis in explaining the asymmetry between normal matter and dark matter. Let's see if it will stand up to future observations.

Scientists Say There May Have Been a Second Big Bang
NOV 11 by VICTOR TANGERMANN

Instead of a single Big Bang that brought the universe into existence billions of years ago, cosmologists are starting to suspect there may have been a second transformative event that could explain the vast abundance of dark matter in the universe.

https://futurism.com/second-dark-big-bang

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A New Possible Explanation for the Hubble Tension
December 1, 2023

Introduction:

(Eurekalert) The universe is expanding. How fast it does so is described by the so-called Hubble-Lemaitre constant. But there is a dispute about how big this constant actually is: Different measurement methods provide contradictory values. This so-called “Hubble tension” poses a puzzle for cosmologists. Researchers from the Universities of Bonn and St. Andrews are now proposing a new solution: Using an alternative theory of gravity, the discrepancy in the measured values can be easily explained - the Hubble tension disappears. The study has now been published in the Monthly Notices of the Royal Astronomical Society (MNRAS).

Conclusion:

In fact, another research group recently measured the average speed of a large number of galaxies that are 600 million light years away from us. “It was found that these galaxies are moving away from us four times faster than the standard model of cosmology allows,” explains Sergij Mazurenko from Kroupa’s research group, who was involved in the current study.
…
This is because the standard model does not provide for such under-densities or “bubbles” - they should not actually exist. Instead, matter should be evenly distributed in space. If this were the case, however, it would be difficult to explain which forces propel the galaxies to their high speed.

“The standard model is based on a theory of the nature of gravity put forward by Albert Einstein,” says Kroupa. “However, the gravitational forces may behave differently than Einstein expected.” The working groups from the Universities of Bonn and St. Andrews have used a modified theory of gravity in a computer simulation. This “modified Newtonian dynamics” (abbreviation: MOND) was proposed four decades ago by the Israeli physicist Prof. Dr. Mordehai Milgrom. It is still considered an outsider theory today. “In our calculations, however, MOND does accurately predict the existence of such bubbles,” says Kroupa.

If one were to assume that gravity actually behaves according to Milgrom’s assumptions, the Hubble tension would disappear: There would actually only be one constant for the expansion of the universe, and the observed deviations would be due to irregularities in the distribution of matter.

Read more here: https://www.eurekalert.org/news-releases/1009834

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JWST And Hubble Agree on The Universe's Expansion, and It's a Major Problem
by Michele Starr
March 12, 2024

Introduction:

(Science Alert) A new, precise measurement of the expansion rate of the Universe is in, and it's serving up a huge cosmic pickle.

Using Hubble data and new observations from the James Webb Space Telescope (JWST), a team led by physicist Adam Riess of Johns Hopkins University has confirmed that previous measurements are correct after all, despite years of debate.

Based on immense distances from our Solar System to Cepheid variable stars and Type Ia supernovae, which are used to create a 'cosmic distance ladder', our Universe does indeed appear to be expanding at 73 kilometers per second per megaparsec – a rate known as the Hubble constant.

The problem is that other methods of measuring the Hubble constant return different measurements. Scientists thought that this Hubble 'tension', as it is known, might be a human error. A new measurement with a very high confidence level – 8 sigma – means that something else is the issue.

"With measurement errors negated, what remains is the real and exciting possibility that we have misunderstood the Universe," Riess says.

Read more here: https://www.sciencealert.com/jwst-and- ... -problem

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New Research Suggests that Our Universe Has No Dark Matter
March 15, 2024

Introduction:

(Eurekalert) The current theoretical model for the composition of the universe is that it’s made of ‘normal matter,’ ‘dark energy’ and ‘dark matter.’ A new uOttawa study challenges this.

A University of Ottawa study published today challenges the current model of the universe by showing that, in fact, it has no room for dark matter.

In cosmology, the term “dark matter” describes all that appears not to interact with light or the electromagnetic field, or that can only be explained through gravitational force. We can’t see it, nor do we know what it’s made of, but it helps us understand how galaxies, planets and stars behave.

Rajendra Gupta, a physics professor at the Faculty of Science, used a combination of the covarying coupling constants (CCC) and “tired light” (TL) theories (the CCC+TL model) to reach this conclusion. This model combines two ideas — about how the forces of nature decrease over cosmic time and about light losing energy when it travels a long distance. It’s been tested and has been shown to match up with several observations, such as about how galaxies are spread out and how light from the early universe has evolved.

This discovery challenges the prevailing understanding of the universe, which suggests that roughly 27% of it is composed of dark matter and less than 5% of ordinary matter, remaining being the dark energy.

Read more of the Eurekalert article here: https://www.eurekalert.org/news-releases/1037861

For a technical presentation of the study results as presented in The Astrophysical Journal: https://iopscience.iop.org/article/10.3 ... 57/ad1bc6

[caltrek]

Giant Structure Lurking in Deep Space Challenges Our Understanding of The Universe
by Michele Starr
May 12, 2024

Introduction:

(Science Alert) A colossal structure in the distant Universe is defying our understanding of how the Universe evolved.

In light that has traveled for 6.9 billion years to reach us, astronomers have found a giant, almost perfect ring of galaxies, some 1.3 billion light-years in diameter. It doesn't match any known structure or formation mechanism.

The Big Ring, as the structure has been named, could mean that we need to amend the standard model of cosmology.

The discovery, led by astronomer Alexia Lopez of the University of Central Lancashire, was presented at the 243rd meeting of the American Astronomical Society in January, and is reported in a pre-print paper available at arXiv.

It's the second giant structure discovered by Lopez and her colleagues. The first, called the Giant Arc, is actually in the same part of the sky, at the same distance away. When the arc's discovery was announced in 2021, it puzzled astronomers. The Big Ring only deepens the mystery.

Read more here: https://www.sciencealert.com/giant-str ... universe

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New Research Support Predictions of Modified Gravity Theory as an Alternative to Dark Matter
June 17, 2024

Introduction:

(Eurekalert) Tobias Mistele, a post-doctoral scholar in the Department of Astronomy at Case Western Reserve’s College of Arts and Sciences, pioneered a revolutionary technique using “gravitational lensing” to delve into the enigmatic realm of dark matter. He found that the rotation curves of galaxies remain flat for millions of light years with no end in sight.

Scientists have previously believed that the rotation curves of galaxies must decline the farther out you peer into space.

Traditionally, the behavior of stars within galaxies has puzzled astronomers. According to Newtonian gravity, stars on the outer edges should be slower due to diminished gravitational pull. This was not observed, leading to the inference of dark matter. But even dark matter halos should come to an end, so rotation curves should not remain flat indefinitely.

Mistele’s analysis defies this expectation, providing a startling revelation: the influence of what we call dark matter extends far beyond previous estimates, , stretching at least a million light-years from the galactic center.

Such a long-range effect may indicate that dark matter—as we understand it—might not exist at all.

Read more here: https://www.eurekalert.org/news-releases/1048445

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Tiny Bright Objects Discovered at Dawn of Universe Baffle Scientists
June 28, 2024

Introduction:

(Eurekalert) UNIVERSITY PARK, Pa. — A recent discovery by NASA’s James Webb Space Telescope (JWST) confirmed that luminous, very red objects previously detected in the early universe upend conventional thinking about the origins and evolution of galaxies and their supermassive black holes.

An international team, led by Penn State researchers, using the NIRSpec instrument aboard JWST as part of the RUBIES survey identified three mysterious objects in the early universe, about 600-800 million years after the Big Bang, when the universe was only 5% of its current age. They announced the discovery today (June 27) in Astrophysical Journal Letters.

The team studied spectral measurements, or intensity of different wavelengths of light emitted from the objects. Their analysis found signatures of “old” stars, hundreds of millions of years old, far older than expected in a young universe.

The researchers said they were also surprised to discover signatures of huge supermassive black holes in the same objects, estimating that they are 100 to 1,000 times more massive than the supermassive black hole in our own Milky Way. Neither of these are expected in current models of galaxy growth and supermassive black hole formation, which expect galaxies and their black holes to grow together over billions of years of cosmic history.

“We have confirmed that these appear to be packed with ancient stars — hundreds of millions of years old — in a universe that is only 600-800 million years old. Remarkably, these objects hold the record for the earliest signatures of old starlight,” said Bingjie Wang, a postdoctoral scholar at Penn State and lead author on the paper. “It was totally unexpected to find old stars in a very young universe. The standard models of cosmology and galaxy formation have been incredibly successful, yet, these luminous objects do not quite fit comfortably into those theories.”

Read more here: https://www.eurekalert.org/news-releases/1049884