The crisis in Cosmology--Solved?

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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

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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