SoylentNews

hubie [soylentnews.org] writes:

For millennia, humans have been fascinated by the mysteries of the cosmos [princeton.edu]:

Unlike ancient philosophers imagining the universe's origins, modern cosmologists use quantitative tools to gain insights into its evolution and structure. Modern cosmology dates back to the early 20th century, with the development of Albert Einstein's theory of general relativity.

Now, researchers from the Atacama Cosmology Telescope (ACT) collaboration have submitted a set of papers to The Astrophysical Journal featuring a groundbreaking new map of dark matter distributed across a quarter of the sky, extending deep into the cosmos, that confirms Einstein's theory of how massive structures grow and bend light over the 14-billion-year life span of the universe.

The new map uses light from the cosmic microwave background (CMB) essentially as a backlight to silhouette all the matter between us and the Big Bang.

"It's a bit like silhouetting, but instead of just having black in the silhouette, you have texture and lumps of dark matter, as if the light were streaming through a fabric curtain that had lots of knots and bumps in it," said Suzanne Staggs [princeton.edu], director of ACT and Henry DeWolf Smyth Professor of Physics at Princeton University. "The famous blue and yellow CMB image [nasa.gov] [from 2003 [princeton.edu]] is a snapshot of what the universe was like in a single epoch, about 13 billion years ago, and now this is giving us the information about all the epochs since."

[...] "We have mapped the invisible dark matter distribution across the sky, and it is just as our theories predict," said co-author Blake Sherwin [cam.ac.uk], a 2013 Ph.D. alumnus of Princeton and a professor of cosmology at the University of Cambridge, where he leads a large group of ACT researchers. "This is stunning evidence that we understand the story of how structure in our universe formed over billions of years, from just after the Big Bang to today.'

He added: "Remarkably, 80% of the mass in the universe is invisible. By mapping the dark matter distribution across the sky to the largest distances, our ACT lensing measurements allow us to clearly see this invisible world."

[...] Sherwin added, "Our results also provide new insights into an ongoing debate some have called 'The Crisis in Cosmology.'" This "crisis" stems from recent measurements that use a different background light, one emitted from stars in galaxies rather than the CMB. These have produced results that suggest the dark matter was not lumpy enough under the standard model of cosmology and led to concerns that the model may be broken. However, the ACT team's latest results precisely assessed that the vast lumps seen in this image are the exact right size.

"While earlier studies pointed to cracks in the standard cosmological model, our findings provide new reassurance that our fundamental theory of the universe holds true," said Frank Qu, lead author of one of the papers and a Cambridge graduate student as well as a former Princeton visiting researcher.

[...] The pre-print articles highlighted in this release are available on act.princeton.edu [princeton.edu] and will appear on the open-access arXiv.org.

Original Submission