Chen Ning Yang is not completely opposed to China’s construction of a hadron collider. He just thinks the future of the collider is unclear. The most important point is that the price/performance ratio is not high. There is no need to spend hundreds of billions to build something like this that is not within our capabilities. High energy physics belongs to fundamental physics. The level of human understanding of elementary particles determines the highest level of human science and technology. The Large Hadron Collider is the most important tool for studying high-energy physics, so countries always want to build larger colliders.
CEPC is expected to have a circumference at least twice that of the LHC, or about 60 kilometers, and the collider will also be buried 50 to 100 meters underground. Building such a huge collider is estimated to cost more than 100 billion yuan. Often, the estimated cost of building such a large collider is insufficient and additional investments may be required. After completion, a large amount of money will be invested in equipment maintenance every year.
CEPC is like a funding black hole, which will absorb a large amount of scientific research funds and make other scientific research fields in urgent need of funds stretched. Even with such a huge capital investment, CEPC may not be able to make major discoveries in a short period of time. At present, theoretical physics has not made a substantial breakthrough, nor can it point out a clear direction for experiments. It costs so much just to get it.
Although China's economy has made tremendous progress in the past few decades, we are still a developing country and there are still more places to spend money. Professor Yang Zhenning believes that these hundreds of billions of dollars should be used to solve many pressing problems currently facing our country, such as education, medical care and environmental protection. Professor Yang Zhenning is not opposed to the development of high-energy physics. It's just a matter of waiting until the right time in the future to build a large collider.