At the invitation of the Department of Astronomy, on November 6th, world-renowned cosmologist and astrophysicist, academician of the Royal Society, Professor Ogden of Durham University, director and founder of the Institute of Computational Cosmology, principal founder and leader of the VIRGO Alliance Professor Carlos S. Frenk, one of the people, was the guest of the 141st Masters Forum in the Li Zhengdao Library Auditorium, bringing a wonderful report entitled “From nothing to everything: how the universe is formed”.
The report begins with four questions about cosmology: 1. How the universe begins; 2. What constitutes the universe; 3. How the universe evolved into today's state; 4. What the future of the universe will be. Modern cosmology is based on many laws of physics that have been confirmed by experiments on Earth. What do you get when you apply the laws of physics to the universe? Before answering these questions, Professor Carlos briefly introduced the galaxies in our universe, which is where our planet exists, and uses a video made of real data to explain to us the grand spatial scale from the solar system to the Milky Way. . First, Professor Carlos explained that our universe consists of 5% barium, 25% dark matter and 70% dark energy, and briefly analyzes the properties of these materials.
Then, Professor Carlos introduced an effect gravitational lens effect in the universe. Through an analog video, we showed how this effect is produced: how the lens celestial body deflects the light emitted by the source celestial body through the gravitational effect. Through these deflections we can "weigh" the lens objects and get their mass. This led to the introduction of the so-called "dark matter" that we are particularly interested in. Professor Carlos then showed us the fascination of dark matter, and mentioned the PandaX dark matter detection experiment in our country and looked forward to it. After that, Professor Carlos told us through an animation that “nothing” in physics is not really “nothing”. There are still quantum fluctuations in the vacuum, and it is these fluctuations that have evolved into our current level. The distinct universe, this is precisely the meaning of the topic "From Nothing to Everything". Later, the professor showed us the evolutionary history of the universe from the big bang, leading us to swim in the vast universe.
Among them, the cosmic microwave background radiation is an important concept in cosmology, an important clue to reveal the origin of the universe, and a direct evidence of the big bang theory. Mr. Carlos explained the principles, discoveries and observations of the cosmic microwave background and showed the audience the infinite mystery of cosmology in the context of the work of this year's Nobel laureate Mr. Peebles. Mr. Carlos then explained the next period of the origin of the universe, the formation of galaxies, and demonstrated the galaxies generated by computer numerical simulations for the audience. When the audience marveled at the material in the universe, because the disturbances were gathered from the dust into the galaxy, we I also lamented that the development of human science and technology can make this process vivid and vivid.
At the end of the lecture, Mr. Carlos introduced us to the development prospects of astronomy and encouraged all the students present to climb the scientific peak.
In the interactive session, Professor Carlos answered questions about how dark matter is realized in numerical simulations, particle collisions in the universe vacuum produce gamma rays, and dark matter interacts with other substances. He listened very carefully to the questions and made a rigorous and careful answer, which made the audience feel sincere admiration.
At the end of the lecture, the organizing committee of the Master Forum presented Professor Carlos S. Frenk with a carefully crafted clay figure as a souvenir to express his heartfelt gratitude and sincere wishes to the university. He was also invited to leave the master's handprints and inscriptions, and took photos with the members of the master forum.
[Guest Profile]
Carlos S. Frenk graduated from Cambridge University with a Ph.D. in 1981. He joined the Institute of Computational Cosmology at Durham University in 2001 and served as the director of the Institute. In the same year, he became a professor of basic physics at Ogden. Carlos is also a Principal Investigator at the Virgo Alliance. So far, Carlos has published 450 academic papers. The total number of citations has exceeded 80,000, including more than 120 high-cited articles. He has been invited to participate in more than 200 international conferences and reports. In 2015, Carlos was named one of the “World's Most Influential Scientists”. Carlos is committed to cosmology research. Together with other scientists, he uses supercomputers to build cosmological models, tries to understand the birth and evolution of the universe, and uses physics to describe the universe from a simple "perturbation" to the billions seen today. Complex structures composed of stars and galaxies.
[Background introduction]
Cosmology is dedicated to solving the most basic scientific questions: When was our universe formed? What constitutes the universe? How are the structures and galaxies in the universe formed? In order to answer these questions, cosmology has made tremendous progress in the past few decades, and we have entered the era of precise cosmology. Recent observations have shown that our universe contains many components: baryons, dark matter, and dark energy. Large-scale galaxy surveys show the structure of the universe, while high-precision supercomputer numerical simulations can reproduce the formation and evolution of the universe, linking the early universe to current observations. This allows us to reproduce the evolution of the universe from one second after the big bang to today. However, many of the most basic issues, such as the nature of dark matter and dark energy, remain unresolved.
Carlos S. Frenk is a world-renowned cosmologist and computational astrophysicist who led Virgo, the international cosmological numerical simulation alliance. Through the N-body numerical simulation, he proposed a universal formula to describe the dark matter halo density profile, and established a framework for the formation of dark matter halos under the cold dark matter model. Currently, he led the Institute of Computational Cosmology at Durham University to develop a high-precision numerical simulation of fluid dynamics, Eagle, to explore the relationship between galaxies formation and evolution and dark matter. It is also hoped to detect small-mass dark matter halos through gravitational lenses and radio observations, and further distinguish between cold dark matter and warm dark matter models, thereby limiting cosmology.
