Why did spiral galaxies disappear from the supergalactic plane?

An international research team led by Durham University (UK) and Helsinki University (Finland) has discovered the answer to why spiral galaxies like the Milky Way are rare in part of the supergalactic plane that is our local universe. It’s a huge flat structure spanning almost a billion light years, and our galaxy is embedded within it. The supergalactic plane is rich in bright elliptical galaxies, but is noticeably lacking in bright spiral arm disk galaxies. Researchers believe this is due to differences in environmental conditions inside and outside the aircraft. In dense galaxy clusters on supergalactic planes, galaxies often interact and merge, resulting in spiral galaxies turning into elliptical galaxies and supermassive black holes growing. At the same time, galaxies far away from the plane can evolve in relative isolation, maintaining their spiral structure.

The research results were published in the journal Nature Astronomy. They are based on data from the supercomputer simulator SIBELIUS, which tracks the evolution of the universe over 13.8 billion years, from the beginning of the universe to the present day. Unlike most cosmological simulations, SIBELIUS strives to accurately reproduce observed structures, including supergalactic planes, and the final simulations are surprisingly consistent with telescopic observations of the Universe. Co-author of the study, Professor Carlos Frenk from Durham University, emphasized that the distribution of galaxies at the supergalactic level is indeed unusual. The simulation shows how the standard model of the universe, based on the assumption that most of the mass is cold dark matter, can reproduce the most prominent structures in the universe, including impressive structures including the Milky Way. I am.

The unique separation of spiral and elliptical galaxies in the local universe has been known since the 1960s and deserves special attention. This feature is widely recognized in the scientific community, particularly by his 2019 Nobel Prize winner, cosmologist Jim Peebles. Dr. Til Sabara, lead author of the study, said their work shows that the well-known mechanisms of galaxy evolution are also at work in this unique cosmic environment. The supercomputer simulations were performed on his Cosmology Machine supercomputer (COSMA 8) at Durham University’s Institute for Computational Cosmology.

source: https://www.nature.com/articles/s41550-023-02130-6