Breaking News: Scientists Measure Total Amount of Matter in the Universe
In a groundbreaking discovery, an international team of scientists has successfully determined the total amount of matter in the universe. The research, led by scientists from Japan’s Chiba University, revealed that matter accounts for 31% of the total matter and energy in the universe, with the remaining composition being dark energy.
This question of how much matter exists in the universe has long intrigued cosmologists. The team, publishing their findings in the Astrophysical Journal, used well-established techniques to compare the observed number and mass of galaxy clusters per unit volume with numerical simulation predictions.
Dr. Mohamed Abdullah, the first author of the study, explained that while cosmologists believe that only 20% of total matter is comprised of ordinary particles such as stars, galaxies, atoms, and life, the remaining 80% is made up of dark matter. The nature and composition of dark matter are still a mystery, although it may consist of subatomic particles yet to be discovered.
To overcome the challenge of measuring the mass of galaxy clusters, the team employed an indirect method using the Mass Richness Relation (MRR). By observing the number of galaxies within each galaxy cluster, they were able to estimate the total mass.
By comparing the observed cluster number and mass per unit volume with predictions from numerical simulations, the research team found that matter accounts for 31% of the entire universe. This result aligns closely with the observations of the Planck satellite’s Cosmic Microwave Background (CMB).
Anatoly Klypin from the University of Virginia noted that the higher the proportion of matter in the universe, the greater the formation of galaxy clusters. However, accurately measuring the mass of galaxy clusters is challenging since the majority of matter is dark matter and cannot be directly observed through telescopes.
This groundbreaking discovery represents the first successful use of spectroscopy to accurately determine the distance to each galaxy cluster and the actual member galaxies. This finding confirms the power of the Mass Richness Relation (MRR) technique in determining the parameters of the universe.
Further research and observations are needed to unlock the mysteries of dark matter and provide a more comprehensive understanding of the universe. The implications of this discovery will undoubtedly shape future research in cosmology and astrophysics.
(Note: This article has been reprinted with permission from the Taipei Planetarium)