China News Service, Beijing, January 23 (Reporter Sun Zifa) Is the 13.8 billion years since the Big Bang the true age of the universe?
The mystery of the age of the universe has long attracted concern, and the astronomical community has continued to conduct related research.
The latest news from the National Astronomical Observatory of the Chinese Academy of Sciences said that the National Astronomical Observatory of the Chinese Academy of Sciences' research team Guo Qi, together with collaborators from many Chinese and foreign institutions such as the University of Chinese Academy of Sciences, Shanghai Jiao Tong University and Leiden University in the Netherlands, discovered a group of massive galaxies using the Sloan Spectral Redshift Survey. The central satellite galaxy pair has co-directional motion relative to the central galaxy. This is significantly different from the predictions of current cosmological models, suggesting a younger universe. It also means that the true age of the universe is younger than currently predicted based on the cosmic microwave background.
Galaxies falling into a massive galaxy group (Image source: Liao Shihong). The red area is a massive galaxy group, and the yellow circles are galaxies falling along large-scale fiber-like structures. They are relative to the central galaxy. Movement in the same direction.
National Astronomical Observatory of the Chinese Academy of Sciences/Photo provided
This important astronomical research paper was recently published online in the international professional academic journal Nature Astronomy.
Guo Qi's research team said that the standard cosmological model has been successful in many aspects. Under its framework, small structures are formed first, and then merge step by step to form larger and larger structures.
Massive galaxy groups and galaxy clusters are the largest structures in the universe, and their dynamic equilibrium states reflect the evolution of the universe.
Astronomers can usually use the dynamic information of satellite galaxies to infer the dynamic state of galaxy groups and galaxy clusters.
In this study, with the help of the Sloan Spectroscopic Redshift Survey, the research team measured the dynamics of satellite galaxy pairs around 813 massive galaxy groups, with a special focus on their motion correlation along the line of sight.
The research team found that the satellite galaxy pairs distributed on both sides of the central galaxy tend to have the same direction relative to the radial velocity deviation of the central galaxy. The co-directional motion of the satellite galaxy pairs usually indicates that they are moved along the large-scale fiber structure. The process of accretion.
At the same time, the excess of codirectional motions in satellite galaxies is also predicted in numerical simulations based on current cosmological models, but at a much lower scale than in observations.
Compared with the predicted values of the two numerical simulations, the observed data in this study showed a large excess.
The proportion of co-moving satellite galaxy pairs changes with the opening angle: the solid black line with dots is the observation result, the blue line and the red line are the theoretical simulation prediction results, the black dotted line is the random distribution, and the shaded area is the bootstrap standard error range.
National Astronomical Observatory of the Chinese Academy of Sciences/Photo provided
The research team said that the huge difference between observations and theoretical predictions indicates that massive galaxy groups formed later in the real universe than predicted based on the cosmic microwave background radiation, and therefore also indicates a younger universe.
On the one hand, it tends to support a higher Hubble constant than predicted by the cosmic microwave background and closer to measurements of the Hubble constant in the nearby universe, challenging current cosmological models.
On the other hand, the deviation of baryonic matter processes in current numerical simulations also provides a possible explanation.
They believe that future research needs to combine further development of theory and observation to finally determine the age of the universe.
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