University of Waterloo researcher creates world's largest 3D map of the universe

James Marshall
July 22, 2020

"The difficulty lies in getting that third dimension, that distance to the galaxy. we do that by measuring the redshift of the galaxy, that is how fast the galaxy is moving away from us", says Percival, also an associate faculty member at the Perimeter Institute of Theoretical Physics.

The Sloan Digital Sky Survey (SDSS) publishes a comprehensive analysis of the largest three-dimensional map of the Universe ever created, which fills the most significant voids of our exploration on the history of cosmos.

"These studies allow us to connect all these measurements into a complete story of the expansion of the Universe", said Will Percival of the University of Waterloo in the statement.

An global team of scientists recently released the largest three-dimensional map ever created of the universe, the result of years' worth of examinations that helped to offer a clearer understanding of the cosmos over an 11-billion-year period. Officials in the study speculated that the accelerating expansion may be the result of the mysterious, undetectable force known as dark energy.

The work carried out by eBOSS astrophysicists specifically examines the universe from a time when it was about 300,000 years old, pinpointing on observations of galaxies and energy-packed quasars to better define the universe's structure. For five years, scientists from SDSS have worked to discover what happened during that period of time, and used the information to get one of the most important advances in the cosmology of the last decade.

This accelerated expansion seems to be due to dark energy, consistent with Albert Einstein's general theory of relativity but extremely hard to reconcile with our current understanding of particle physics.

In particular, the eBOSS team's measurement of the current rate of expansion of the universe, the previously mentioned Hubble's Law, is about 10 per cent lower than the value found from distances to nearby galaxies. It's "unlikely that this 10% difference is random due to the high precision and wide variety of data in the eBOSS database", according to the EPFL.

The SDSS map is shown as a colourful rainbow, located in the observable Universe (external sphere, which shows fluctuations in the microwave cosmic background).

"These newest maps from eBOSS show it more clearly than ever before". It's called dark energy and it's expanding the universe at a fast rate. Julian Bautista, a researcher in the Institute of Cosmology and Gravitation at the University of Portsmouth.

In creating the portion of the map that dated back some 6 billion years, researchers zeroed in on large, red galaxies, and from there, they jumped to examining younger, blue galaxies for more distant eras. To go back even further, they used quasars, galaxies whose supermassive black hole is extremely luminous.

"The analogy for the world would be if we had a map, for example, of Canada", Percival explained, "But that map just contained locations of the tops of the mountains".

Each of the samples required careful analysis in order to remove contaminants, and reveal the patterns of the Universe. "Its been an incredible team resource and I'm so happy to see it come to fruition", says Percival.

"In 2012, I launched the eBOSS project with the idea of producing the most complete 3D map of the Universe throughout the lifetime of the Universe, implementing for the first time celestial objects that indicate the distribution of matter in the distant Universe, galaxies that actively form stars and quasars", said Professor Jean-Paul Kneib, Director of the Laboratory of Astrophysics at the Ecole Polytechnique Fédérale de Lausanne (EPFL).

Other reports by Click Lancashire

Discuss This Article