On August 26, a massive glacier and mountainside collapse struck the Himalayan region along the border between Nepal and Tibet, China. Huge volumes of ice, rock, soil and floodwater surged downstream through the river valleys at high speed, destroying roads, bridges, homes and hydropower infrastructure.

The disaster occurred in a high-altitude, mountainous area with extremely complex terrain, making rescue operations exceptionally difficult. As of August 31, the reported numbers of deaths and missing people in Nepal and Tibet were still rising rapidly, with figures varying between different sources. According to Reuters, the death toll had approached 800, while more than 3,000 people remained missing. Many of those missing were hydropower workers, local residents and travellers making pilgrimages to the Himalayas.

What makes this disaster particularly shocking is not only the scale of the destruction, but the fact that it occurred in an environment that is changing rapidly.

Scientists have long warned that global warming is making high-altitude regions increasingly unstable. Glacier retreat, thawing permafrost, changes in mountain structures, and the growing number of unstable glacial lakes may all increase the risk of landslides, ice avalanches and floods that were once relatively rare.

In other words, this is not a disaster that can simply be understood as “ice suddenly melting on the mountain.” It is more like a warning sign: when climate change begins to alter an entire mountain range, it is never only the ice on the mountains that is affected. The entire lifeline made up of mountains, rivers, farmland, cities, dams and people is affected as well.

And this lifeline connects nearly two billion people across Asia.

The “Third Pole” Is Losing Its Ice

When people talk about global warming, the Arctic and Antarctic are usually the first places that come to mind. Shrinking Arctic sea ice and collapsing Antarctic ice shelves have become some of the most recognisable images of climate change. But in another part of the world lies another vast frozen region.

Stretching from Afghanistan and Pakistan through India, China, Nepal and Bhutan, the Hindu Kush Himalaya contains the largest reserves of snow and ice outside the Arctic and Antarctic, and is therefore often referred to as the “Third Pole.”

These glaciers are not simply enormous blocks of ice sitting on mountains. They form a vast natural reservoir. Snow accumulates during winter and gradually melts during the warmer seasons, supplying water to rivers downstream. Many of Asia’s major rivers are connected to this high-mountain snow and ice system, including the Indus, Ganges, Brahmaputra, Mekong, Yangtze and Yellow rivers. This means that the ice in the Himalayas ultimately flows toward some of the most densely populated regions in Asia.

The problem is that this natural reservoir is shrinking. Research published in 2026 by the International Centre for Integrated Mountain Development (ICIMOD) shows that glacier loss across the Hindu Kush Himalaya has accelerated significantly since 2000, with the rate of ice loss now roughly twice what it was before 2000. Between 1990 and 2020, the region’s glacier area decreased by around 12%, while estimated ice volume fell by approximately 9%.

Even more concerning is that these changes are not happening at a steady rate. They are accelerating.

ICIMOD points out that only a small proportion of glaciers currently have long-term monitoring data that meet global standards. This means that although scientists already know conditions are worsening, there is still insufficient data to determine exactly how quickly changes are occurring in some areas. This is one reason why the crisis at the “Third Pole” can be easily overlooked.

Changes in the Arctic and Antarctic can be shown directly to the world through satellite images. But Himalayan glaciers are separated by mountain peaks thousands of metres high, narrow river valleys and remote terrain. As glaciers gradually become thinner, the changes often do not immediately attract global attention.

Until ice, rock and water suddenly come crashing down a valley together.

The Conditions for Mountain Collapse Are Changing

When discussing this disaster, it is also important to avoid an oversimplified explanation: not every flash flood can simply be described as being “caused by global warming.” Landslides and glacier collapses are usually the result of multiple interacting factors, including geological structure, rainfall, snowmelt, glacier fractures, rock stability and earthquakes.

Preliminary research into this disaster suggests that a massive collapse involving both glacier ice and bedrock produced a high-speed flow of ice, rock and soil, which eventually developed into a devastating flood. The collapse even generated seismic signals equivalent to a magnitude 5.2 earthquake.

But another issue deserves even greater attention.

Climate change is altering the underlying conditions in high-mountain regions. As temperatures rise and glaciers retreat, terrain that was once stabilised by ice and snow becomes increasingly exposed. Thawing permafrost may also weaken the stability of rocks and mountain slopes. At the same time, melting glaciers can create or enlarge glacial lakes, some of which are naturally dammed by loose glacial debris known as moraines.

If one of these natural dams breaks, enormous amounts of water can be released downstream within a very short period, creating what is known as a Glacial Lake Outburst Flood, or GLOF. Climate change may therefore not be the sole cause of any individual landslide, but it may be making the entire high-mountain environment increasingly fragile. And this growing vulnerability can ultimately be transmitted through rivers to places hundreds of kilometres away.

A Dangerous Paradox

One of the most easily misunderstood aspects of the Himalayan glacier crisis is that the phrase “melting glaciers” sounds as though it should mean there will be more water.

In the short term, that may indeed be true. As glaciers melt more quickly, more water flows into rivers. Some river basins may therefore enter what scientists call “Peak Water,” the stage at which glacier meltwater reaches its maximum level.

But glaciers are not unlimited reservoirs. As the volume of ice continues to shrink, there will eventually be less ice available to melt during the summer. Once glaciers retreat beyond a certain point, the amount of water rivers receive from them will actually begin to decline.

This creates a seemingly contradictory future: in the short term, there may be too much water; in the long term, there may not be enough.

This transition is especially important for rivers that depend heavily on glacier meltwater.

During dry and hot seasons, glacier meltwater often plays an important role in maintaining a stable base flow in rivers. As glaciers gradually disappear, river flows may become increasingly seasonal and extreme. Water levels may surge during the rainy season, while stable water supplies become scarce during the dry season. This means the problem facing the Himalayas is not simply the next flood.

The real long-term question is whether, once glaciers retreat beyond a critical point, people downstream will discover that the natural reservoir they have always relied on no longer holds enough water.

From Flash Floods to the Dinner Table

These hydrological changes will first affect mountain communities. Farmers need stable water supplies for irrigation, cities rely on rivers for drinking water, hydropower stations require consistent flows, while mountain roads, bridges and electricity transmission infrastructure are often built along river valleys. A single river can therefore support agriculture, cities, energy and transport at the same time.

When floods suddenly increase, farmland, roads and dams may be destroyed. When water levels fall during the dry season, agriculture and hydropower generation may also suffer. This is particularly important for food security across Asia.

The river systems of the Hindu Kush Himalaya support an enormous agricultural population. For downstream countries, the issue is not simply whether water exists, but when it arrives, how quickly it arrives, and whether it can be stored and used. If the rainy season and snowmelt period bring more floods, while the growing season or dry season experiences water shortages, agriculture may face both “too much water” and “too little water” at the same time.

The same is true for hydropower. The Himalayan region has enormous hydropower potential, and Nepal, India and Tibet in China have all invested heavily in related projects. However, hydropower plants are often located in narrow river valleys, which are themselves high-risk areas for flash floods, debris flows and landslides.

This disaster once again highlights the contradiction: humans hope to obtain lower-carbon energy through hydropower, yet as the high-mountain climate becomes more extreme, energy infrastructure designed according to historical hydrological data may face entirely new risks.

For Australia, This Is Not “Someone Else’s Disaster”

The Himalayas may seem so far from Australia that it is difficult to imagine any direct connection between the two. Australia does not have massive Himalayan-style glaciers, nor would the melting of a glacier in Nepal directly cause flooding in Australia.

But that does not mean Australia is unaffected. On the contrary, this disaster provides a clear example of why climate risks today can no longer be understood purely within national borders.

The First Connection Is Australia’s Place in the Indo-Pacific

Australia is itself an Indo-Pacific country. Climate disasters across South Asia, Southeast Asia and the Pacific can ultimately affect Australia through food, energy, trade, population movements and humanitarian crises.

When changes in Himalayan glaciers alter the amount of water flowing through Asian rivers, countries such as India, Nepal, Pakistan, Bangladesh and others may be affected first. But these countries are also important diplomatic, economic, trade and strategic partners for Australia. The Australian Government has long regarded climate change as an important security and development issue in the Indo-Pacific and has incorporated climate resilience, food security and water management into regional cooperation.

There is a very practical reason behind this: a climate disaster in one country does not necessarily remain within that country.

Declining agricultural production can affect commodity prices. Floods can damage ports and roads. Energy shortages can push up costs. Long-term water shortages may force people to leave their homes. Eventually, all of these changes can enter global supply chains.

The Second Connection Is That Australia Is Facing Its Own Climate Challenges

Australia’s challenges are, of course, completely different from those of the Himalayas. But they share one extremely important feature: water resources are becoming increasingly unstable.

Australia’s Bureau of Meteorology has stated that climate change is increasing drought risks in some regions. In southern Australia in particular, a warmer climate can make droughts more frequent or severe, while cool-season rainfall has declined in some areas over recent decades.

At the same time, Australia is also experiencing extreme rainfall and flooding. Data from the Australian Government’s State of the Environment report shows that the intensity of short-duration extreme rainfall has increased in some areas in recent years, while daily rainfall associated with thunderstorms has also increased compared with 1979.

Australia is therefore not simply moving from “water shortages” to “more water.” Instead, it may increasingly experience both extremes: long periods without enough rain, followed by too much rainfall in a very short period.

This has a certain similarity to the paradox of “flooding and long-term water shortages” now facing the Himalayas. The geography of the two regions is completely different, but the underlying problem is the same. Cities, farms, dams and transport systems were built around relatively stable historical climate conditions. Now, those historical averages themselves are becoming less reliable.

The Third Connection Is Australia’s Agriculture and Food Security

Australia is one of the world’s major agricultural exporters. On the surface, Australia could appear to be a “beneficiary” of a global water crisis. If other major agricultural producers experience declining output because of water shortages, demand for Australian exports could even increase.

But the situation is not so simple.

Australian agriculture itself depends heavily on water, and the global food market is an interconnected system. If densely populated agricultural regions in Asia are disrupted by changes to glaciers and rivers, global food prices and trade patterns may also be affected. The challenges facing Australian farmers would then extend beyond local water supply. Could global market prices fluctuate sharply? Will demand from Asian buyers change? Could certain agricultural products see higher demand because production has declined elsewhere? Could energy, fertiliser and transport costs be affected by climate disasters?

This is why climate change should not be understood as merely a local weather issue for Australian agriculture. It is also a global market issue.

The Fourth Connection Is Energy and Infrastructure

Australia is also rapidly expanding renewable energy. Low-carbon energy sources such as solar, wind and hydropower are seen as important parts of the energy transition. But climate change also reminds us that energy systems cannot focus only on “how to reduce carbon emissions.” They must also consider whether they can continue operating under extreme climate conditions.

Hydropower stations in the Himalayas may face flash floods and debris flows. Australia may face bushfires, heatwaves, floods, droughts and extreme storms. This means future energy infrastructure needs to meet two conditions at the same time: it must be low-carbon, and it must be resilient.

If an energy facility can reduce emissions but cannot withstand future extreme weather, then it may still become part of the climate risk itself.

This lesson is particularly important for Australia, because the country is currently at a critical stage of its energy-system transition.

The Fifth Connection Is That Australia Cannot Treat Climate Change as Only an Environmental Policy Issue

This may be the most important lesson the Himalayan disaster offers Australia. In the past, discussions of climate change in Australia have often focused on emissions reduction, energy policy and environmental protection. But the impacts of climate change have already extended far beyond environmental policy. They involve diplomacy, defence, agriculture, energy, infrastructure, migration, humanitarian assistance and national security.

Australian parliamentary research has identified climate change as an important security risk in the Pacific region, while the Australian Government continues to support climate adaptation and resilience in Pacific countries through regional cooperation.

The same logic can be extended to South Asia.

If the Himalayan water crisis continues to worsen, Australia may in the future face greater regional humanitarian assistance demands, more complicated diplomatic coordination and greater pressure in managing cross-border disasters.

And this is not simply a government issue. Australian society itself has deep connections with South Asia. A large number of Australian residents have South Asian backgrounds, and extensive family, business, education and tourism networks connect the two regions.

This disaster has already provided a very direct reminder of that connection. Although it occurred in the Himalayas, Australians were also among those reported missing or affected. As of August 31, the Australian Government was providing consular assistance and participating in related rescue and aid efforts, while Australian media reported that dozens of Australians were missing in the disaster. Climate risks, therefore, will only become increasingly globalised.

What We Really Need to Watch

Perhaps the most unsettling aspect of this disaster is not how many roads, bridges and homes it destroyed, but the fact that it gave us a brief glimpse of a world that is usually difficult to see.

Thousands of metres above sea level, glaciers are shrinking and mountains are changing. Yet when ice and rock suddenly collapse, the consequences may be felt by villages, cities, farmland and hydropower stations tens or even hundreds of kilometres away.

This is one of the most easily misunderstood aspects of climate change. It is not simply a change in global average temperature. It is a chain reaction: melting glaciers can create dangerous glacial lakes; a glacial lake outburst can become a flash flood; a flash flood can destroy hydropower stations and roads, affecting energy supplies and the economy; long-term glacier retreat can reduce dry-season water supplies; agricultural water shortages can turn into problems of food prices and supply; when people lose access to land and water, they may begin to migrate; and when rivers cross national borders, water resources can become issues of diplomacy and security.

All of this can begin with a small piece of ice at the top of a mountain.

What is happening in the Himalayas, therefore, should not be understood simply as a disaster in Nepal or Tibet. It is a glimpse of the changes taking place across the Third Pole. Ice is disappearing in the Arctic and Antarctic, while Asia’s high-mountain glaciers are also retreating at an accelerating rate. ICIMOD has warned that current glacier loss already poses a long-term threat to water security across Asia.

For Australia, perhaps the greatest lesson from this disaster is not whether Australia will experience the same kind of flash flood. Australia faces its own climate risks, including droughts, heatwaves, extreme rainfall, floods, bushfires and sea-level rise.

All of these risks are reminding us of the same thing: the climate of the past may not be the climate of the future.

When cities, agriculture, energy systems and national policies continue to be designed around what was considered “normal” over the past several decades, the greatest danger may not be a single extreme event, but the gradual transformation of extreme events into the new normal.

The ice in the Himalayas will not flow directly to Australia. But water crises, food risks, population movements, supply-chain disruptions and regional security challenges caused by climate change can cross national borders and eventually reach Australia.

That is why, when the world once again turns its attention to the flash floods in Nepal and Tibet, what we need to look at is not only what the floodwaters have swept away. We also need to look up at the mountain range that is gradually losing its ice and snow. Because when the “Third Pole” begins to melt, it is never just one mountain that changes.

Chinese mathematicians Wang Hong and Deng Yu were awarded the Fields Medal, known as the “Nobel Prize of Mathematics,” in July, sparking widespread discussion in China and around the world about the rise of Chinese mathematics in the 20th century. Wang Hong solved the famous three-dimensional Kakeya conjecture, while Deng Yu tackled the sixth of Hilbert’s 23 problems, proposed at the International Congress of Mathematicians in 1900, and achieved significant results.

I studied mathematics at university, as well as the history of mathematical development, and have also worked in mathematics education and training. Naturally, I am pleased to see Chinese mathematicians receiving international recognition. Through this feature, I hope to look back with readers at the arduous path taken by Chinese mathematical research over the past century. I believe this was not a smooth, linear path of upward development, but rather one marked by ruptures, the passing of the baton overseas, and subsequent new beginnings.

Many early mathematicians received their training outside China before returning to China to work hard to establish the foundations of mathematical research, only to suffer devastating setbacks during the Cultural Revolution. We then saw Chinese mathematicians who had settled overseas demonstrate the mathematical talent of the Chinese diaspora and advance mathematical research around the world. In the contemporary era, China has gradually developed a selection culture centred on mathematics competitions, against which a new generation of mathematicians has emerged.

The following section traces this generational journey through several representative figures. I offer this as a tribute to Wang Hong and Deng Yu, and to the Chinese people who have worked hard in mathematical research around the world for more than a century.

I. Pioneering and Interruption: From Xiong Qinglai, Hua Luogeng and Chen Shengshen to Chen Jingrun

The true beginning of modern mathematics in China cannot be separated from a group of early pioneers. They established departments, identified talent, developed academic traditions, and struggled to keep the flame of research alive during difficult times.

Xiong Qinglai (1893–1969) was known as the “Bole of the Chinese mathematical community.” He founded the Department of Mathematics and a research division at Tsinghua University and personally compiled Chinese-language textbooks. More importantly, he had a keen eye for talent. In 1930, after seeing a paper written through self-study by Hua Luogeng in the journal Science, he overcame opposition and brought Hua Luogeng, who had only a junior middle school education, to Tsinghua University as an assistant. This gave him the opportunity to sit in on mathematics classes and develop rapidly. Xiong later recommended him to study at Cambridge. Without this exceptional support, Hua Luogeng’s life trajectory might have been completely different.

Hua Luogeng (1910–1985) embarked on his mathematical career under Xiong Qinglai’s support. Born into a poor family in Jintan, he became a self-taught mathematician. In 1936, on the recommendation of Norbert Wiener during his study visit, Hua Luogeng went to Cambridge to study number theory under the mathematician Hardy, publishing 15 world-class papers within a year. Hua Luogeng later became a professor at the University of Illinois. In 1950, he gave up the favourable conditions he enjoyed in the United States and returned to China, becoming director of the Institute of Mathematics at the Chinese Academy of Sciences. He worked hard to establish China’s own mathematical research capacity and trained young talents, including Chen Jingrun.

During the Cultural Revolution, Hua Luogeng, like many other scientists, came under attack. Afterwards, he shifted significantly towards applied mathematics, actively promoting the “Optimization Method” and “Overall Planning Method.” He led small teams across more than 20 provinces and cities throughout the country, going deep into factories, rural areas and construction sites, applying mathematical methods directly to production practices and serving national economic development. This experience led him from pure theoretical research towards more practical applications and promotion, and became one of the best-known aspects of his later work.

At the same time, Hua Luogeng placed great importance on mathematics competitions from an early stage. After studying the Soviet mathematics Olympiad in the 1950s, he actively advocated for the organisation of mathematics competitions for secondary school students in China. In 1956, pilot competitions began in Beijing, Shanghai and other places. After the end of the Cultural Revolution, in 1978, he personally presided over the national secondary school mathematics competition involving eight provinces and cities, and wrote several popular mathematics booklets for young people. He hoped to stimulate interest and discover talent through competitions. These early efforts planted the seeds for the later Chinese tradition of selecting mathematical talent through competitions, although the highly competitive culture of competitions beginning in primary and secondary schools today only gradually took shape and became extreme after his death.

Chen Shengshen (1911–2004) completed his undergraduate education and early research training entirely in China. He studied at Nankai University (1926–1930) and Tsinghua University, completing his master’s degree at Tsinghua and beginning preliminary research in differential geometry. It was not until 1934 that he went to the University of Hamburg in Germany to pursue his doctorate. It was precisely this foundation established in China that enabled him to quickly emerge on the international stage. After completing his doctorate in Germany, he was invited to the Institute for Advanced Study in Princeton in 1943, where he completed important work. He later taught for many years at the University of Chicago and the University of California, Berkeley, and founded the Mathematical Sciences Research Institute in the United States in 1981. Although he became an American citizen, he remained deeply concerned about mathematics in China. After his first visit to China in 1972, he travelled back and forth frequently. In 1984, he was invited to establish the Institute of Mathematics at Nankai University, helping China reconnect with the international mathematical community. He often said, “Mathematics has no borders, but mathematicians have a motherland.” Chen Shengshen and Hua Luogeng were both leading figures in Chinese mathematics in the 1930s and 1940s. They met at Tsinghua, worked together at Southwest Associated University, and maintained a lifelong friendship.

Chen Jingrun (1933–1996) was a direct continuation of this line of inheritance during difficult times. After being recognised by Hua Luogeng, he was transferred to the Institute of Mathematics of the Chinese Academy of Sciences. Under extremely basic conditions, he made important progress on the Goldbach conjecture and became a symbolic figure of Chinese mathematics during that era.

However, precisely because of his excessive devotion to mathematics, he suffered greatly during political movements. During the Cultural Revolution, Chen Jingrun was criticised as a typical example of someone who “took the path of focusing on expertise while neglecting political ideology,” and was subjected to struggle sessions and isolation. He lived in a room of only about six square metres at the Chinese Academy of Sciences. Without a desk, he would lie on the bed and perform calculations. Despite being physically weak and suffering from multiple illnesses, he endured criticism during the day and secretly conducted research at night. On one occasion, he was so absorbed in a mathematical problem that he forgot the time of a meeting, resulting in harsher criticism.

This experience of being persecuted “because of his love of mathematics” was not an isolated case. During multiple political movements after the founding of the People’s Republic of China, many scientists devoted to academic pursuits were regarded as being “specialised but not politically committed.” Their research was forced to stop and their careers were damaged. The obvious decline and rupture in China’s domestic mathematical development during that period were closely connected to this environment.

This pioneering period suffered a devastating setback during the Cultural Revolution. Many mathematicians, including Hua Luogeng and Chen Jingrun, were attacked and persecuted, while normal research and teaching almost came to a halt. The development of mathematics in mainland China experienced a clear rupture during this period. The first stage of pioneering efforts came to an end.

II. Passing the Baton Overseas: Yau Shing-Tung and Terence Tao

When mathematics in China fell into a low period, Chinese mathematicians who had settled overseas became important successors in carrying the baton.

The trajectory of Yau Shing-Tung (1949–) is almost a complete illustration of “reaching the peak overseas while continuing to give back to China.” He grew up in Hong Kong and later went to the United States for further study, where he studied under Chen Shengshen. He taught at Harvard University for many years and achieved great accomplishments in the international mathematical community. But he never limited himself to the American academic community. Since his first visit to China in 1979, he has spent time in China and Hong Kong almost every year for more than four decades, promoting mathematics education and research, participating in the establishment of multiple mathematics centres, setting up awards and competitions, and helping to cultivate young people. In 2022, he retired from Harvard and returned full-time to Tsinghua University, focusing most of his efforts on cultivating mathematical talent in China. His choice symbolised the completion of a cycle for a generation of overseas Chinese mathematicians: “departure—reaching the peak—return.”

Terence Tao (1975–), meanwhile, represents another form of contribution. Born in Australia and with ancestral roots in Guangdong, he demonstrated extraordinary talent from an early age and became well known in the international mathematical community at a very young age. Unlike Yau Shing-Tung, whose focus was on institutional development, Terence Tao has contributed more through writing, lectures, blogs and public activities, promoting mathematical ways of thinking and research culture around the world. He has allowed many ordinary people to experience the appeal of mathematics and has also become an important role model for the younger generation.

Together, the two demonstrate the role of Chinese-diaspora mathematicians in carrying the baton after the Cultural Revolution: one became deeply involved in rebuilding mathematics within China, while the other enhanced the visibility and appeal of mathematics on a global scale.

III. Contemporary Faces Under Competition-Based Selection: Wei Dongyi, Liu Zhiyu, Wang Hong and Deng Yu

Entering the 21st century, China gradually developed a selection culture centred on mathematics competitions. Gold medals at the International Mathematical Olympiad and results in national competitions became important tickets to entering top universities. Wei Dongyi, Liu Zhiyu, Wang Hong and Deng Yu are all representatives who grew up in this environment, yet they have taken completely different paths.

Wei Dongyi (1991–) won full-score gold medals at the IMO twice. After being admitted to Peking University through direct recommendation, he chose to remain in China and is now a teacher at Peking University. Quiet and focused, he devotes almost all his energy to mathematics. Although prestigious overseas universities once extended offers to him, he chose to stay. His path is one of “putting down roots locally,” participating in the internal development of Chinese mathematics through long-term, stable research and teaching.

Liu Zhiyu (1988–) was also an IMO full-score gold medalist. After graduating from Peking University, he could have gone to MIT for further study, but instead chose to become a monk. More than a decade later, he returned to secular life and turned towards psychological counselling and related work. His story reminds us that mathematical talent does not necessarily have to follow the path of “continuing to conduct research.” The high-pressure elite education system and expectations associated with early achievement may lead people to reflect more deeply on the definition of “success.” His choice is not a failure, but another exploration of the meaning of life.

Wang Hong (1991–) and Deng Yu (1989–), meanwhile, represent the most common high-potential pathway today: completing their undergraduate studies in China (both studied at Peking University), then going overseas for further education, and ultimately achieving important accomplishments on the international stage. In 2026, the two were awarded the Fields Medal simultaneously, becoming the first mathematicians holding Chinese citizenship to receive the honour. Their experiences demonstrate that China’s current competition and undergraduate selection systems are capable of identifying world-class potential talent, but the most important breakthroughs often still need to be achieved in more mature research environments overseas.

The different choices made by these four people form a picture of the contemporary era: some choose to stay and deepen their work locally, some step outside the academic path to question the meaning of life, and some go overseas and achieve breakthroughs within global networks. None of these choices is superior to another.

IV. What These People Tell Us About Changes in Chinese Mathematics

Looking back over the past century, we can broadly identify several distinct generations:

The pioneering generation (Xiong Qinglai 1893–1969, Hua Luogeng 1910–1985, Chen Shengshen 1911–2004, Chen Jingrun 1933–1996): They worked to establish the foundations, but suffered severe disruption during the Cultural Revolution. Hua Luogeng turned towards application and promotion in his later years and planted the early seeds for mathematics competitions; Chen Jingrun, meanwhile, suffered severe persecution because of his devotion to mathematics, becoming a microcosm of the circumstances faced by intellectuals during that era.

The overseas baton-passing generation (Yau Shing-Tung 1949–, Terence Tao 1975–): They achieved accomplishments on the international stage while giving back to China in different ways.

The competition-based selection generation (Liu Zhiyu 1988–, Deng Yu 1989–, Wei Dongyi 1991–, Wang Hong 1991–): They grew up under a selection system centred on mathematics Olympiads. The system has been able to consistently produce young people with high potential, but how to truly transform this potential into original research remains a challenge.

From Xiong Qinglai to Hua Luogeng, then from Hua Luogeng to Chen Jingrun; from Chen Shengshen to Yau Shing-Tung; and then to today’s Wei Dongyi, Wang Hong and Deng Yu, this line of inheritance has experienced ruptures but has never been completely broken.

Today, Chinese mathematics has a huge population base and a rigorous selection system, while an increasing number of young people are choosing to stay or return. However, a research environment that genuinely allows long-term exploration, tolerates failure and does not rush for immediate results is still gradually taking shape.

The Fields Medal is not the end, nor is it a simple scorecard of national strength. What truly matters is whether talented young people can grow in a relatively relaxed and intellectually deep environment, while being allowed to make different choices in life.

From Hua Luogeng to Wang Hong and Deng Yu, this journey has already come a long way. But the road ahead may require even more patience and tolerance than the road already travelled.

Mr. Raymond Chow

On September 15, 2026, a new regulation will come into effect. The provision is not long, containing only 19 articles; but any one of them is enough to make anyone holding a Chinese passport, or anyone who has ever had a connection to Chinese identity, reconsider the weight of the words “returning home.”

When “Going Back for a Meeting” Becomes “Unable to Return”

In March this year, two young Chinese technology entrepreneurs returned from Singapore to Beijing for a meeting at the invitation of China’s National Development and Reform Commission. They were Xiao Hong, co-founder of artificial intelligence company Manus, and its chief scientist, Ji Yichao — a star AI company that had only last year been described by observers as “the second DeepSeek moment.” At the time, Meta was preparing to acquire the company for approximately US$2 billion.

After the meeting ended, the two were told that they could not leave China during the regulatory review. They were free to travel within the country, but they could not leave.

Neither Xiao Hong nor Ji Yichao had committed a crime, nor had they been charged. There had not even been any formal legal proceedings. Yet at that moment, the passports in their hands were effectively useless.

If you think this has nothing to do with you — perhaps it is worth thinking again. Because on July 31, 2026, the State Council of China published the Regulations of the State Council on Exit and Entry Administration (State Council Decree No. 841), which will formally take effect on September 15. One entirely new provision in these regulations could turn experiences like those of Xiao Hong and Ji Yichao from “special cases” into something expressly authorised by law.

Nineteen Articles, One Provision Enough to Change the Rules

The official name of the regulation is the Regulations of the State Council on Exit and Entry Administration. Signed by Premier Li Qiang, it contains 19 articles. The government says its purpose is to “regulate exit and entry administration, safeguard the lawful rights and interests of persons entering and leaving the country,” and “safeguard national sovereignty, security and development interests.”

It sounds highly official, but what is truly worth paying attention to is Article 4. It sets out three circumstances in which Chinese citizens “shall not be permitted to leave the country.” The first two — receiving administrative penalties for fraud involving exit and entry documents, and engaging in criminal activities overseas that endanger national security — are, to some extent, continuations of existing practices. The real new element lies in the third provision:

“Where a person violates regulations on export controls, technology import and export administration, or other relevant provisions, and may endanger national industrial security or technological security, the competent departments of the State Council, such as the commerce authorities, may decide not to permit the person to leave the country.”

At first glance, this sentence may seem unremarkable. But when broken down, there are three points that should concern every overseas Chinese person:

First, there is no time limit. The first two provisions specify “six months to three years,” whereas the third provision makes no mention whatsoever of an expiry period. In theory, a person could be prohibited from leaving the country indefinitely.

Second, the decision is given to commerce authorities without requiring a court. Such a restriction does not result from a judicial process, but from a decision by an administrative authority. There is no trial, no confrontation, and not necessarily any opportunity for a lawyer to intervene.

Third, the words “may endanger” leave the interpretation entirely in the hands of those enforcing the rule. The regulation itself does not provide any specific technology list, nor does it specify which industries or activities constitute a threat to “industrial security.” Today, it may be artificial intelligence and semiconductors; tomorrow, it could be any industry. And the scope can be expanded by administrative authorities at any time — an individual’s freedom to leave the country is not protected by this provision, but instead depends on the authorities’ judgement at the time.

The cases of Xiao Hong and Ji Yichao are effectively a preview of this new provision. At the time, the National Development and Reform Commission’s request for the two to remain in China had not invoked Article 4, because the regulation had not yet taken effect. But the logic was exactly the same: reviewing an acquisition involving the transfer of technology, while restricting the parties involved from leaving the country. After September 15, this approach will have an explicit legal basis. The U.S. House Select Committee on the Strategic Competition between the United States and the Chinese Communist Party described the incident as sending a message: “There is no such thing as a truly ‘private’ technology company in China.”

Three Names, Three Ways of Being Trapped

The legal provisions may sound abstract, but over the past decade, too many real people have demonstrated through their own loss of freedom just how far China’s exit controls can go.

Cheng Lei: “I Haven’t Seen a Tree in Three Years”

Cheng Lei moved from Hunan to Australia with her family when she was ten. She studied commerce at the University of Queensland before returning to China, where she became a financial presenter for the state-run CGTN. On August 13, 2020, she was taken away by national security officers at the headquarters of China Central Television in Beijing. She would not return for three years.

There was no public trial and no formal announcement of the charges. Even her family and friends did not know what she had allegedly done. It was not until she was released and returned to Melbourne in 2023 that China’s Ministry of State Security confirmed for the first time that she had been charged with “illegally providing state secrets to overseas entities” and sentenced to two years and 11 months — a sentence announced only after she had already completed it.

While in prison, Cheng Lei wrote a letter to the Australian people: “I was allowed only ten hours outdoors a year,” and “I haven’t seen a tree in three years.” In her book, she recalled quietly reciting the names of places she had visited or driven past in Australia while in prison — reminding herself that she was still a living person.

Cheng Lei’s story reminds us of one thing: having once been a public figure in China’s state media, having once been trusted and employed by the Chinese government, does not mean you are immune. Identity has never been a one-way protective shield.

Gui Minhai: A Nationality That Was “Restored”

Gui Minhai, a shareholder of Hong Kong’s Causeway Bay Books, became a naturalised Swedish citizen in 1996. In 2015, he suddenly “disappeared” while travelling in Thailand, before later “reappearing” at an unknown location in mainland China. In 2018, he was taken away for a second time while travelling by train to Beijing, accompanied by Swedish diplomatic personnel.

In 2020, the Ningbo Intermediate People’s Court sentenced him to ten years in prison for “illegally providing intelligence to overseas entities.” The court’s announcement stated that Gui Minhai had “lawfully restored Chinese nationality upon his own application” in 2018.

The Swedish government’s response was clear: under Swedish law, renouncing or restoring nationality must be formally approved by the Swedish Migration Agency. Gui Minhai had never gone through such a procedure. Under Swedish law, he had never ceased to be a Swedish citizen. In other words, China unilaterally declaring that he had “become Chinese again” served a very clear purpose — once his Chinese nationality was “restored,” in the eyes of Chinese law, he was simply a Chinese citizen residing in China, leaving foreign consular authorities with no basis to intervene.

This is not an isolated practice. Just days after the new regulations were announced, a Chinese businessman who had lived in Japan was reportedly detained after returning to China to visit family. It was reported that his Chinese nationality had similarly been “restored,” and that he was restricted from leaving the country for as long as ten years. Because the incident was submitted anonymously and was based on a single account, it has not been possible to fully verify the claim. But commentators have pointed to a more important fact: even if the specific account is questionable, the mechanism and precedent of “forced restoration of nationality” do genuinely exist — the Gui Minhai case in 2018 had already established a precedent. China’s Nationality Law stipulates that restoration of nationality is approved by the Ministry of Public Security. Who has their nationality “restored,” and when, is entirely subject to the interpretation of the public security authorities. Those affected may only learn about it afterwards, or may not know at all.

The purpose of this practice is straightforward: once someone has had their Chinese nationality “restored,” in the eyes of Chinese law, they are simply a Chinese citizen residing in China, meaning foreign governments’ consular protection naturally does not apply. More than ten years have now passed since the Gui Minhai incident. On the tenth anniversary of his abduction in October 2025, Sweden’s Foreign Minister still had to personally raise the matter with Chinese Foreign Minister Wang Yi and demand his release. Ten years later, there has still been no progress, and it remains unclear where he is actually being held.

For Hong Kong-born people living in Australia, this precedent is particularly concerning: even if they have held Australian citizenship for many years, if Chinese authorities unilaterally declare that their Chinese nationality has been “restored,” they could potentially lose the protection of Australian consular assistance in an instant. From the perspective of international law, such a unilateral determination may itself constitute a violation of the Vienna Convention on Consular Relations. In practice, however, those affected often have limited effective avenues of appeal.

Richard O’Halloran: A Man Who Was Never Involved in the Dispute

This case may not be widely known, but it best demonstrates how fragile “innocence” can be in the face of an exit ban.

Irish businessman Richard O’Halloran had only joined the company shortly before a commercial dispute completely unrelated to him broke out. Yet when the company became involved in civil litigation, he was prohibited from leaving China — trapped for three years, from 2019 to 2022. The international protection organisation Safeguard Defenders has pointed out that such cases are not uncommon. Dozens of foreigners have reportedly been prevented from leaving China because of civil or commercial disputes involving their companies, many of whom had no direct connection to the disputes themselves.

Another widely reported case involved a Singaporean executive at the U.S. due diligence firm Mintz Group, who was similarly restricted from leaving China in connection with the company’s business investigations. Analysts have said bluntly that exit bans completely tilt the balance of power in commercial disputes — once one side holds the card of “not allowing the other party to leave,” the bargaining power becomes fundamentally unequal.

For a Chinese person doing business in Australia and maintaining commercial ties with China, this case is particularly relevant — you do not have to commit a crime, or even personally participate in a dispute. Simply because your company, business partner, or even former employer becomes involved in civil litigation in China, you could potentially become trapped there without knowing when you will be able to return home.

It is worth noting that such exit bans are, under Chinese law, mostly not part of criminal proceedings, but an administrative measure attached to civil litigation. According to statistics from the international research organisation Safeguard Defenders, at least 14 laws and dozens of regulations, judicial interpretations and policy documents in mainland China involve this type of border control. In the absence of transparency, the impression is that various government departments, and even local neighbourhood committees, can request that law enforcement authorities place someone under border control. Even more troubling is this: putting someone on a border-control list can be extremely easy, while removing them can be exceptionally difficult. There have been analyses of individual businessmen becoming trapped under indefinite border controls simply because the task force originally established to investigate them had disbanded before the restrictions were lifted — effectively leaving no one with the authority, or even the memory, to sign off on their release.

These Are Not Isolated Incidents, But the Same Logic

Cheng Lei, Gui Minhai, O’Halloran, Xiao Hong and Ji Yichao — five cases that appear completely different in nature (espionage charges against a journalist, “treason” charges against a publisher, a commercial dispute, and a technology export review) — actually share the same underlying logic: administrative authorities can determine whether a person is allowed to leave China without a public trial, without a clear time limit, and without transparent avenues for redress.

In the past, this logic was scattered across different laws and departmental powers. Enforcement standards were unclear, and outsiders could only piece together the bigger picture through individual cases. Now, Article 4, Clause 3 of the Regulations of the State Council on Exit and Entry Administration formally turns this logic into an administrative provision with legal authority, explicitly granting the power to commerce authorities — a body that has previously had less direct involvement in exit controls.

The historical context of this change is not difficult to understand. As technological competition between China and the United States intensifies, rare earths, batteries, artificial intelligence, semiconductors and advanced materials have become key battlegrounds for export controls. Preventing the outflow of critical technologies and talent is a clear policy priority for the Chinese government. The Manus incident shook the industry precisely because it demonstrated that even if a company’s headquarters have moved to Singapore and its founders have relocated there, simply returning to China for a meeting, while its technology is still considered to have originated in China, could result in them suddenly becoming trapped. As one commentator put it vividly: “Human capital is no longer mobile; it is geofenced.”

This national-security-first approach will not necessarily stop at artificial intelligence and semiconductors. The regulation does not list any specific industries. The interpretation of the words “may endanger” lies entirely with the enforcing authorities, and the scope can be expanded at any time. A provision that appears unrelated to you today could suddenly apply to you tomorrow because of the industry you work in or a transaction you participate in.

Three Thousand Years of the Middle Kingdom, and After the Roman Empire: A Collision of Two Concepts of Borders

To understand why Gui Minhai could have his nationality “restored,” or why Xiao Hong and Ji Yichao could still be restricted from leaving China after relocating to Singapore, perhaps we need to look at the deeper historical context. This may not be the only explanation, but it is certainly a framework often used by scholars of China as a reference point.

Traditional Chinese conceptions of Tianxia were not based on the modern international-law concept of “sovereign states, each possessing fixed borders.” Within the imperial system, China viewed itself as the centre of civilisation, while surrounding peoples existed within relationships of tribute or assimilation. The distinction between identities was not based on a clearly defined legal border, but on the distinction between “Chinese civilisation and the barbarians” — whether one identified with or was attached to this civilisational centre.

This way of thinking continued into the modern era. Overseas Chinese were traditionally referred to as “Huaqiao” — Chinese people residing overseas, rather than immigrants who had completely severed their connection. Under this underlying cultural logic, “once Chinese, always Chinese” is not merely a slogan, but a deeply rooted worldview: bloodline and cultural origins are regarded as the true basis of identity. A foreign passport has never been regarded within this framework as an absolute point of separation.

By contrast, the Western modern concept of the sovereign state gradually developed through centuries of fragmentation and restructuring following the collapse of the Roman Empire. After Rome fell, Europe entered a long period of feudal division, with blurred borders and overlapping loyalties. The logic that “each state possesses a fixed territory, equal sovereignty and non-interference in internal affairs” only began to take shape with the 1648 Peace of Westphalia. After several centuries of development in international law, it evolved into today’s modern logic that nationality is a clear legal boundary: once a person changes nationality, their former country no longer has the right to claim them as its citizen. Giving up one nationality and acquiring another is a legal fact mutually recognised by both sides, and cannot be unilaterally overturned because of bloodline or place of birth.

This comparison helps us understand an apparent contradiction: China, as a member state of the United Nations, formally accepts the modern system of sovereign states and, in order to maintain the clear legal boundary of “not recognising dual nationality,” is meticulous in its legal texts. Yet in the Gui Minhai case, the Chinese government simply stated that he had “restored Chinese nationality upon his own application,” thereby unilaterally redefining a person who had never lost his Swedish nationality under Swedish law as Chinese.

This approach uses the language of modern nationality law on the surface, but at its core is closer to a pre-modern concept of civilisational identity in which “if you are ethnically Chinese, you can never truly leave.” For Chinese Australians accustomed to the Western understanding that nationality is a clear legal boundary, this is particularly important to recognise.

Your Background Determines Your Risk

The impact of these regulations on the Chinese community in Australia is not uniform. Because of differences in birthplace, passport history and identity recognition, people from different backgrounds face significantly different levels of actual risk.

People born in Hong Kong face relatively high risks. China considers Hong Kong part of its territory and does not recognise British colonial rule as having legally severed Chinese identity. Even if they hold a foreign passport and have become Australian citizens, they may still have a significant chance of being regarded as people with “connections to Chinese identity” when entering mainland China, and therefore be subject to the exit restrictions. Those who hold a Home Return Permit, or who can otherwise demonstrate connections to Hong Kong or mainland China, should exercise particular caution — the Gui Minhai-style “restoration of nationality” already has a precedent.

Chinese people who migrated to Australia from Southeast Asia — Malaysia, Indonesia, Vietnam, Singapore and others — generally face lower risks, but that does not mean zero risk. Most ethnic Chinese in these regions have been settled there for multiple generations and hold passports of those countries, which China recognises as independent sovereign states. Generally speaking, those who have never held a People’s Republic of China passport or household registration are less likely to be directly subject to provisions concerning Chinese citizens being prohibited from leaving the country. However, China may still traditionally regard people of Chinese heritage as “overseas Chinese,” and in extreme circumstances — particularly where sensitive industries are involved — they may still attract additional attention.

People who migrated to Australia from Taiwan face a particularly sensitive and unique risk. China claims sovereignty over Taiwan and does not recognise Taiwan as an independent country. People holding Taiwanese passports or identity documents are often placed under a special administrative framework when entering mainland China, rather than simply being treated as “foreigners.” If they are involved in technology exchanges or commercial activities, or are deemed to “potentially endanger national security or industrial security,” the potential risk of being restricted from leaving China cannot be ignored.

Australian permanent residents or citizens who currently hold or have previously held Chinese passports or household registration face the highest risk. Regardless of their original place of birth, these individuals are the most likely to be regarded as Chinese citizens and therefore face the greatest risk of being directly subject to Article 4.

For ordinary people who are simply visiting family, travelling, and have no connection whatsoever to technology or export controls, the risk is relatively low. Those who genuinely need to be more alert are people with technology backgrounds, cross-border business dealings, or those who frequently travel using Chinese-related identities.

Conclusion: This Is About More Than One Journey

The emergence of the Regulations of the State Council on Exit and Entry Administration is a product of technological competition between China and the United States and a national-security-first mindset. But it also continues a deeper tradition — throughout Chinese history, China has never truly been a country of completely “free movement.” From the maritime bans of the Ming dynasty to today’s entry and exit administration, control over the movement of people has never truly disappeared.

For every Chinese person living in Australia, these regulations serve as a reminder of one thing: cross-border identity has never been a one-way choice. Your birthplace, your passport history and your current nationality can all affect how the other side defines who you are — and that power of definition may not be in your hands.

Cheng Lei was once a public figure in Chinese state media. Gui Minhai once believed Swedish nationality was a protective shield. Xiao Hong and Ji Yichao once believed that moving their company to Singapore meant they had completed their “decoupling.” Before the incidents happened, each of them probably never imagined that they would become the next case.

September 15 is approaching. Understanding the contents, remaining compliant and carefully assessing the risks are the most practical approaches for now — replacing simple anxiety or disregard with calmness and preparation.

It is important to emphasise that the purpose of this article is neither to create panic nor to urge everyone to sever their ties with China from now on. The everyday family visits and travel of the vast majority of ordinary people are not expected to be directly affected. What truly needs attention is where the boundaries of the rules lie, how transparent their enforcement is, and whether your own background and activities could potentially fall into the category of “sensitive” one day. Understanding the risks does not mean giving up family ties or one’s roots. On the contrary, it is hoped that every reader can make their own choices with a clear understanding of the situation.

Because for every overseas Chinese person who once believed they had “already left,” what is at stake has never been merely one journey. It is about how securely we can establish our lives and livelihoods between different systems and frameworks of identity. This is a question worth every reader and every family seriously considering before September 15.