Despite the fact that the construction of the CEPC is on the agenda, the discussion of the LHC has been unabated! Since the 1970s, Yang's opposition to the construction of the LHC has never changed. In the 1990s, the United States launched the SSC (Superconducting Super Collider), and world public opinion was in an uproar, and at this time, China embarked on the construction of the LHC, which directly triggered a major discussion!
What are colliders for?
Rutherford used ? particle scattering to discover the nucleus, and has since discovered the proton! The particle is a helium nucleus consisting of two protons and two neutrons, which is hit at high speed by the nucleus of the atom will be knocked out of something, scientists can observe the characteristics of this collision out of the material to know the secrets of the material inside.
Scientists later found that the natural state of decay of ? particles are no longer enough, so the invention of gas pedals, in the magnetic field constraints, the electric field will be positively charged protons accelerated to extremely high speeds to hit the atomic nucleus, the opening of the great discovery of high-energy particle physics, the physicist Gell-Mann also discovered the existence of quarks, to the 1960s and 1970s until the golden age of high-energy particle physics, basically has been the Standard Particle Model of the space one by one to fill in the blanks. Subsequent larger colliders under construction have verified various hypotheses proposed in the Standard Particle Model! For example, the LHC verified the existence of the God particle: the Higgs boson in 2013!
In September 2012, the Institute of High Energy proposed the construction of the CEPC-SppC, a CEPC-SppC larger than any other collider, with seven times the energy of the LHC, a diameter of 50-70 kilometers, and a cost of more than 30 billion RMB!
Why did Yang oppose the construction of the LHC?
The collider is indeed very good, for the discovery of the microscopic world, without the collider inch by inch, but its construction costs are extremely high, no economic strength is never, so the 1970s to build a collider, Yang Zhenning categorically expressed opposition, that build a decade behind the West's collider is not as good as to put the money into the basic construction, and this strategy has been a success, and since then the basic The research program has been vigorously developed, laying a solid foundation for the later 863 program.
We have the money now, so why aren't we building?
Yang has always been unequivocally opposed to building colliders, but from the 1970s to the 21st century, the reasons have been different:
The party is over.The party is over, the golden age of high-energy particle physics has passed, this is the central idea given by Yang Zhenning when he gave a speech in the auditorium of the National University of Science and Technology (NUST) on April 29, 2019, in fact, this sentence Yang Zhenning has said in the eighties, the golden time of high-energy particle physics has passed!
Students in the auditorium of the National University of Science and Technology
The big framework of particle physics has already been built, such as symmetry, Raschel's quantity, path integral, canonical field, reorganization, spontaneous symmetry breaking, effective field theory, and so on have been very mature to make a big achievement, there is no groundbreaking theoretical support is impossible, of course, not to say that the particle physics has come to the end of the road, there are also such as supersymmetry, magnetic monopoles and other topology, and so on. Symmetry, magnetic monopoles and other topology-related concepts, Majorana fermions, extra dimensions and so on are still a blank slate.
But in the golden age of particle physics, a world-class discovery could be made in a few years or even months! But now in this post-particle physics era, the only way to produce results is to keep throwing money at it. For example, the LHC cost 70 billion RMB, and its discovery of the Higgs boson in 2013 was indeed very important, but overall, it was not as big as the results of a tiny gas pedal in the 1960s.
So Yang believes that further down the line, what is invested is 100 percent of the money, and what is returned may not even be 1 percent! Moreover, Yang believes that the top talents currently working on particle physics are all in Europe and the United States, and we may have to hire someone to work on such a big project for us?
Additionally from the U.S. SSC gas pedal and the European LHC gas pedal construction experience, the funds exceeded the standard 3-4 times is the norm, and even 5-10 times is not unexpected, CEPC early cost estimate 200 yuan, of that the actual cost is likely to be more than 100 billion, which is a bottomless pit!
What is the reasoning of the proponents again?
Biography of Wang Yifang
China's leading figure in high-energy physics, he discovered the third mode of neutrino oscillation in Daya Bay, Daya Bay neutrino experiment results were selected as one of Science's top ten breakthroughs of the year, the discovery of the first two modes of neutrino oscillations of the scientists have received the Nobel Prize, so Wang Yifang is also the world's physics community in the next few decades is the most likely to win the Nobel Prize! in the next few decades in the global physics community.
Reasons for supporting the construction
Wang Yifang's reasons are undoubtedly very strong, for example, Yang Zhenning believes that the feast is over and Wang Yifang disagrees, he believes that the current Standard Model of particle physics is only a valid theory in low-energy scenarios, and that it is necessary to continue to develop deeper theories, which need to be supported by high-energy gas pedals, because the deeper discoveries will be revealed by more precise measurements of the Higgs particle. which will be revealed by more precise measurements of the Higgs particle!
CEPC can also measure the self-coupling of the Higgs particle and determine the form of the vacuum phase transition in which the Higgs field is involved, which has important implications for the early evolution of the universe. If new forms of Higgs particle coupling, new accompanying particles, non-point-structured Higgs particles, or other deviations from the Standard Model are discovered, there is still a bright future ahead with a second phase to build a large proton collider!
And the construction of CEPC can increase the acceleration of infrastructure, such as cryogenic field, superconducting equipment construction, etc., these projects will lead to another wave of infrastructure, which is a virtuous cycle, there is no crowded funding, lack of funds and other phenomena, but will feed the basic research, China's scientific research foundation can be further improved.
Should a high-energy gas pedal be built?
Particle physics in the end or not, in addition to Wang Yifang and Yang Zhenning talk, in fact, the vast majority of people do not have the right to speak, after all, this is the future of things who do not know, only from a certain aspect of a simple analysis!
Low-temperature engineering field
CEPC's scale is very large, there will be a super volume of infrastructure projects invested, no doubt this will indeed increase GDP, promote economic development, but CEPC's localization rate in the end and geometry? Especially in the field of CEPC high-end superconductivity, most of the technical level is still a foreign monopoly, as well as peripheral such as vacuum pumps, gauss meter, leak detector also rely on foreign imports!
And we are also difficult to obtain the technology through imported equipment, the domestic technology in this area did not develop, but let the foreign manufacturers to pick up a big bargain, which will result in a wall of flowers outside the wall of the results. But the construction of CEPC will also promote the development of domestic cryogenic engineering, in the level of aerospace technology and the medical industry (nuclear magnetic **** vibration, etc.) and the transportation industry (magnetic levitation) will be a long way to go.
Funding and research funding ratio
According to academician Wang Yifang's cost assessment, it will require about 36 billion yuan, and according to the experience of the LHC and SSC, it is likely to be more than 100 billion, but China's total investment in basic scientific research in 2016 was only 82.2 billion yuan, accurately speaking, high-energy particle physics is only a small branch of the development of basic scientific research, so why should it consume almost all the expenses to take care of this direction?
Particle Physics Experiment Development Roadmap
But regardless of the views of the two sides, the construction of CEPC has been put on the agenda, and if there is no accident, we will be able to see the results of CEPC in a decade or so, of course, just results, because whether the results can be produced that's a different matter, maybe it can be produced, perhaps it will be like LHC because of a variety of issues to repair for many years before it began to run! So have some patience folks!