In one of the biggest tests of general relativity to date, a huge team of astronomers has mapped the distribution of nearly 6 million galaxies across 11 billion years of the Universe’s history.
It is, perhaps, the largest test of general relativity to date, spanning most of the 13.8-billion-year history of the Universe – meaning that the theory holds up at the biggest scales as well as the smallest.
“Studying the rate at which galaxies formed lets us directly test our theories and, so far, we’re lining up with what general relativity predicts at cosmological scales.”
It’s predictable and measurable and, so far, extremely well constrained and defined by the theory of general relativity.
So scientists keep poking it to see if the Universe’s contents look just how general relativity says it ought to, on all scales.
Albert Einstein’s early 20th-century mathematics, which he developed to explain the gravitational dynamics of the physical universe, is still widely used.
A massive team of astronomers has mapped the distribution of almost 6 million galaxies over 11 billion years of the Universe’s history, in one of the largest tests of general relativity to date.
The way that the cosmic web changes over time and how gravity pulls these galaxies together along its strands in opposition to the Universe’s expansion is exactly what Einstein’s well-known theory predicted.
Given that it covers the majority of the universe’s 13 point 8 billion-year history, it is arguably the largest test of general relativity to date, demonstrating that the theory is valid at both the largest and smallest scales.
Three new preprints of the findings have been posted to arXiv in advance of peer review, and they have been submitted for publication.
“We needed to test that our assumption works at much larger scales, even though general relativity has been very well tested at the scale of solar systems,” says Pauline Zarrouk, a cosmologist at the French National Center for Scientific Research.
As of right now, our findings are consistent with what general relativity predicts at cosmological scales, and studying the rate at which galaxies formed allows us to test our theories directly. “..”.
The universe functions fundamentally due to gravity. Things with mass have a tendency to attract other objects with mass; the strength of this attraction is directly proportional to the mass; and it changes the geometry of space-time around a mass, but we don’t know what it is or why.
It acts as a glue, binding the universe together as well. The majority of the matter in the Universe is dispersed along the strands and nodes of the vast filaments of gravitational fields created by dark matter that stretch throughout the entire Universe in a manner akin to a web.
It is measurable, predictable, and, thus far, very well defined and constrained by general relativity theory. But identifying the theory’s shortcomings may help solve some extremely difficult issues, like the intractable discrepancies between quantum mechanics and classical physics. On all scales, scientists continue to probe the Universe to see if its contents appear as general relativity predicts.
And that leads us to the Dark Energy Spectroscopic Instrument (DESI), led by Lawrence Berkeley National Laboratory and a massive international collaboration that is currently mapping the observable Universe to reveal its greatest mysteries. The instrument has been in use since 2019, and the new findings are based on a thorough and in-depth examination of only the first year’s worth of data.
The DESI Collaboration used that data to map the growth, evolution, and distribution of 5.7 million galaxies and quasars throughout the Universe’s history, starting from the early Universe 11 billion years ago.
They predicted the growth and distribution of the cosmic web using the theory of general relativity and discovered that, on an epic cosmic scale, the Universe has acted as relativity predicts it should. The universe wouldn’t look the same if gravity were added or removed.
The outcome comes after a study published earlier this year that used cosmic remnants of acoustic waves that froze when the atomic fog that surrounded the early Universe cleared to calculate the expansion rate of the Universe. The goal of the DESI Collaboration is to continue to illuminate the Universe’s evolution and, consequently, the enigmatic forces that propel it.
DESI has examined the expansion of cosmic structure for the first time, according to University of Michigan physicist Dragan Huterer. Our ability to investigate modified gravity and enhance constraints on dark energy models is amazing. Furthermore, it’s just the beginning. “..”.
Additionally, the findings imposed limitations on the maximum mass of the neutrino, a particle so “ghostly” that we haven’t been able to weigh it accurately.
Both the survey and the work of the Collaboration are still in progress. The data from the first three years of DESI’s existence is presently being examined by the researchers. When the instrument is finished, it will have gathered information on over 40 million quasars and galaxies.
It is highly anticipated that it will contribute to the elucidation of the nature of dark matter, the enigmatic invisible substance that creates extra gravity in the universe, and dark energy, the enigmatic invisible substance that propels the universe’s fluctuatingly accelerating expansion.
According to physicist Mark Maus of the University of California Berkeley and Lawrence Berkeley National Laboratory, “dark energy makes up another 70 percent of the Universe, and we don’t really know what either one is.” Dark matter makes up roughly 25% of the Universe.
“It is astounding to think that we can answer these important, fundamental questions by taking images of the universe. “.”.
