How galaxies evolve in the cosmic web

An international team of researchers discovered that thread-like "filaments" in the cosmic web play an important role in the evolution of galaxies like our Milky Way.

The cosmic web is a large-scale web-like structure comprising galaxies and the filaments are like bridges connecting the denser regions in the cosmic web.

"We think the cosmic web, dominated by dark matter, formed very early in the history of the universe, starting with small initial fluctuations in the primordial universe," said Behnam Darvish from the department of physics and astronomy at the University of California in the US.

For the study, the team relied on a giant section of the cosmic web first revealed in two big cosmological surveys, namely COSMOS and HiZELS.

They then applied a new computational method to identify the filaments which, in turn, helped them study the role of the cosmic web.

"We were surprised by the crucial role the filaments play in galaxy formation and evolution," added Bahram Mobasher from the University of California.

Because of the complexities involved in quantifying the cosmic web, astronomers usually limit the study of the cosmic web to numerical simulations and observations in our local universe.

Now, the team plans to extend this study to other epochs in the age of the universe to study the role of the cosmic web/filaments in galaxy formation and evolution across cosmic time.

"This will be a fundamental piece of the puzzle in order to understand how galaxies form and evolve as a whole," said David Sobral at the Universidade de Lisboa, Portugal.

The study appeared in the Astrophysical Journal.