05.13.2016 13:51
China Plans World's Largest Particle Collider to Unlock Universe's Mysteries
Supporters say the billion dollar facility will help improve understanding of the origins of matter, but critics warn it could be more expensive than planned
By staff reporters Zhang Yan and Yu Dawei
(Beijing) – China plans to invest US$ 6 billion to build the world's largest particle collider to get a foot in the door of experimental physics dominated by European and American research labs, but some scientists warn it could be a wasteful undertaking.
The blueprint for what scientists call a super collider, an underground facility to smash subatomic particles at high speeds, was drafted in 2014 by scientists at the Institute of High Energy Physics (IHEP) in Beijing. The project, dubbed the "Higgs Factory," aims to build a facility capable of generating millions of Higgs boson particles, which physicists say form the building blocks of the universe.
Scientists at IHEP have completed the design for an underground ring with a circumference of 50 to 100 kilometers that can smash together electrons and positrons, state media reported in October. If built, it would be at least twice the size of the world's largest particle accelerator, a 27-kilometer circular tunnel beneath the Swiss-French border.
The plan is yet to be approved by the central government, but scientists are optimistic that research needed to build the facility can start in late 2016. Construction of the first phase of this Circular Electron Positron Collider is expected to begin in 2021 near Qinhuangdao, a port city in the northern province of Hebei, scientists said.
The second phase of the project, which will upgrade the facility to a proton–proton collider, is set to start by 2040.
The lab could help the country "leap to a leadership position in an important frontier in basic science," wrote David Gross, an American theoretical physicist and Nobel laureate, in a commentary in the Wall Street Journal in September.
The project "would transport physics into a previously inaccessible high-energy realm," wrote Harvard professor Shing-Tung Yau and science journalist Steve Nadis in their book, From the Great Wall to the Great Collider, published in April.
But the plan has hit a snag, with several scientists warning the project might be an unrealistic and wasteful endeavor. The government has also been cautious. It has not given any feedback on IHEP's proposal so far, sources close to the project said.
Doubtful Leap
The discovery of the Higgs boson particle in 2012 was seen by experts as one of the biggest scientific breakthroughs in human history, changing the way we understand our universe, how it originated and its future.
It was found by a team of scientists experimenting at the Large Hadron Collider (LHC) by crashing high-energy proton beams at velocities near the speed of light. This research facility, operated by the European Organization for Nuclear Research, is known as CERN.
However, the accelerator may not be able to generate large quantities of Higgs boson particles to support further studies, said IHEP director Wang Yifang in a 2015 interview with state-run newspaper China Daily.
The "LHC is hitting its limits in terms of energy levels (needed to smash particles)," said Wang. "It seems that it is not possible to escalate the energy (level) dramatically at the existing facility."
CERN said in October that it was working on improving its facilities by 2025.
China's particle accelerator promises to go a step further in unlocking the mysteries of the universe. It will operate at about seven times the energy level of the LHC, said Wang, and will be able to generate large quantities of Higgs boson particles to try to recreate the conditions that followed the Big Bang, one theory that explains the origins of the universe and matter.
Critics, however, doubt this plan. Some theories have proved that the study of particles using high energy collision experiments has almost reached its limits, said Cao Zexian, a physicist at the Chinese Academy of Sciences. "Nobody can be sure that high energy colliders can make new discoveries," and that is why no other country has proposed the construction of a new collider, he said.
Wang says there are several areas in the field of high energy physics that still need to be explored. Countries like the United States are hesitating to build new facilities due to cost concerns amid an economic slowdown, he said.
In the 1980s, the United States started to build what was called a Superconducting Super Collider with a ring circumference of 87.1 kilometers, but the project in the state of Texas was called off in 1993 due to rising costs.
Although many physicists say they want a bigger facility for further research, sluggish economic growth in the United States and debt woes in Europe are preventing governments from investing large sums to develop the field of high energy physics, Michael Riordan, professor of physics at University of California, Santa Cruz, said.
IHFP operates a 220 meter electron-positron collider in Beijing, the largest one in the country, built in 1990.
Chinese authorities may be waiting for more research to show that high energy physics is a promising field of research to invest in. In December 2015, scientists at CERN said the LHC might have discovered a new particle, which cannot be defined using existing laws of physics.
Researchers are expected to publish detailed findings about the new particle by the end of the year, said Xu Cenke, professor of physics at the University of California, Santa Barbara, and their findings will serve as an important reference when Chinese authorities decide whether to go ahead with plans to build a domestic lab.
Weighing the Benefits
The research needed to build the collider will improve technology used in several industries, Wang aid. Some areas that can benefit are cryocooler technology, a cooling technique that can be used to preserve human cells and organs, designing precision machines used on assembly lines and discovering new material to build semiconductors for computer chips, he said.
"Every dollar we spend on the collider will help improve the country's technology capacity," said Wang. Most of the components needed to build the facility will be made domestically by local scientists, he said.
But Cao from the Chinese Academy of Sciences said key components and technologies needed for the project will have to be imported because the country's high-tech research and precision machine development capabilities still lag behind those of developed countries. Most of the money will be spent on buying imported equipment and parts, he said.
Some experts worry that the costs could rise way above the estimated budget. When the LHC was completed, the final bill stood at US$ 9 billion, more than three times the initial budget of US$ 2.6 billion. It also costs more than US$ 1 billion every year to operate and maintain the facility.
Opponents of the projects argued that instead of building a larger collider, the money should be spent on developing other fields of research with a more immediate social impact.
"It is hard to say whether it is right or wrong to invest so much to build a collider," said Cao. "But before that, we can try to improve our computer chips and the tips of ballpoint pens."
(Rewritten by Han Wei)
http://english.caixin.com/2016-05-13/100943237.html