Trump envoy meets PM, raising hopes of a thaw
Ambassador-designate meets with Jaishankar, Doval, and Misri; discussions cover defence, trade, technology, and cooperation on critical minerals; strains in ties stem from tariffs, visa restrictions
The intensity of the meetings with India’s foreign policy leadership is an indicator of the U.S. government’s eagerness to get India-U.S. relations back on the rails after months of strain over the 50% tariffs on Indian goods, visa crackdowns, U.S. pressure over ending India’s Russian oil imports, and differences over the narrative on Operation Sindoor. However, Mr. Modi and Mr. Trump have had two telephone calls in the past month, which have raised hopes they can repair the rupture in ties.
In particular, any move by India to reduce its intake of Russian Ural will be watched closely, with the import level having dipped already despite larger discounts being offered in recent weeks.
Mr. Modi’s praise of Mr. Trump’s Gaza peace proposal and tweets in seven different languages are believed to be aimed at addressing Mr. Trump’s obvious annoyance that India did not join other countries in endorsing him for the Nobel Peace Prize and has denied that the U.S. had any role in ending the Operation Sindoor conflict with Pakistan.
“Discussed the India-U.S. relationship and its global significance,” Mr. Jaishankar posted on social media after the meeting with Mr. Gor, wishing him for his new responsibility in Delhi. According to the Ministry of External Affairs Spokesperson, Mr. Gor and Mr. Misri had a “productive exchange on the India-U.S. Comprehensive Global Strategic Partnership and its shared priorities”.
Mr. Gor is accompanied by Deputy Secretary for Management and Resources Michael J. Rigas, arriving days after the U.S. Senate confirmed his appointment as the U.S. Ambassador to India. His visit is unusual, as according to normal protocol, he would arrive in Delhi, and conduct meetings only after he has presented his credentials to President Droupadi Murmu.
However, the timing of the meeting, just weeks before the ASEAN summit, as well as the unorthodox manner of U.S. diplomacy are seen as reasons for the sudden visit. In particular, Mr. Gor is believed to have conveyed the urgency of finalising the India-U.S. trade agreement at the earliest, before the leaders meet.
According to a U.S. State Department release, Mr. Gor was to be in India from October 9 to 14. However, he attended the Indian Embassy Deepavali party in Washington on October 10 before arriving in Delhi on Saturday for the meetings. According to sources, Mr. Gor will stay on for the next few days for meetings inside the U.S. embassy as well as with other stakeholders in Delhi. He is expected to return at a later date to present his credentials and take charge of the U.S. embassy in Delhi as well as his role in the region.
India-Afghan ties will grow in the coming days: Taliban Minister
India-Afghanistan relations have a bright future, said visiting Afghan Taliban administration’s Foreign Minister Amir Khan Muttaqi on Saturday.
Mr. Muttaqi, the first top-level Taliban leader to be hosted by the famed seminary, Darul Uloom in Deoband, was honoured by the Rector of the Darul Uloom, Maulana Mufti Abul Qasim Nomani.
Mr. Muttaqi described Darul Uloom of Deoband as his group’s “alma mater”.
“God willing, India-Afghanistan relations will advance a lot in the coming days. I am thankful for such a grand welcome and the affection shown by the people of the region and by the students and teachers of Darul Uloom. I am hoping that we will exchange more visits with India in the coming days. My discussion in Delhi was also very good. India-Afghanistan relations will have a bright future and we are about to send our diplomats to Delhi,” said Mr. Muttaqi, following his meeting with the students and teachers at the seminary.
Mr. Muttaqi is on a six-day visit to India.
At the packed venue at Deoband, Mr. Muttaqi took the microphone and said, “Deoband hamara madar-e-ilmi hei (Deoband is our alma mater)”, indicating the role that the tradition of Deoband’s Darul Uloom has played in strengthening the Taliban movement during the years of occupation of Afghanistan under the Soviet era in the 1980s and the U.S.-led NATO in the 21st century.
Darul Uloom Deoband had been the inspiration behind the seminary of Darul Uloom Haqqania in Khyber Pakhtunkhwa in Pakistan. The seminary, started by Abdul Haq, a teacher in Darul Uloom Deoband, was one of the main centres of the Taliban movement during the Soviet occupation of Afghanistan when the Mujahideen fighters fought Soviet troops on Afghan soil. The tradition then spread across the Af-Pak frontiers.
Mr. Muttaqi met External Affairs Minister S. Jaishankar on Thursday and raised the case of Afghan prisoners in Indian jails, and discussed intensifying Indian humanitarian aid to Afghanistan. Following Mr. Jaishankar’s assurance on Friday, the Indian technical mission in Kabul handed over a substantial consignment of humanitarian assistance to the Taliban administration in Kabul on Saturday. The consignment will be sent to the earthquake-hit eastern Afghanistan’s Kunar.
Mr. Muttaqi prayed with a large number of students and teachers and read a Hadith (Prophet’s teachings) alongside the congregation. The special honour bestowed on him at Deoband qualifies him to be a teacher at the seminary.
Grow export-oriented crops, Modi tells farmers
Launching the Dhan Dhaanya Krishi Yojana and the Pulses Self-Reliance Mission, the Prime Minister calls for reducing the dependence on imports and focusing on export-oriented crops
The reforms in Goods and Services Taxes (GST) have resulted in double the savings for rural households and lowered costs on both daily-use items and farming tools, Prime Minister Narendra Modi said here on Saturday while launching two schemes — the Dhan Dhaanya Krishi Yojana and the Pulses Self-Reliance Mission — for the agriculture sector. He asked farmers to not only work towards self-sufficiency but also target the global market by growing export-oriented crops that can reduce imports and boost India’s agricultural exports.
Beyond flour, rice
The Prime Minister said the Pulse Self-Reliance Mission is also a mission to empower future generations. He asked farmers to think beyond flour and rice. “While flour and rice can satisfy hunger, adequate nutrition requires more, and we need to plan for that. Protein is crucial for India’s nutrition today, especially for vegetarians. Protein is one of the things we need. It is equally important for our children, for their physical development as well as mental development,” he said, adding that pulses are the way to go.
“Today, the country imports pulses in large quantities from other countries. And therefore, the Pulse Self-Reliance Mission is crucial,” he said. The scheme is worth more than ₹11,000 crore. The target is to increase the cultivation of pulses by 35 lakh hectares. “This will directly benefit about two crore pulse farmers of the country,” Mr. Modi said.
He said Indian farmers will have to focus on crops that become popular in the world markets. “We have to reduce imports and should not lag when it comes to exports. The PM Dhan Dhanya Krishi Yojana and the Pulse Self-Reliance Mission would play a major role in this,” he said.
Tractor sales
Maintaining that the Centre’s effort is to reduce the expenses of every farmer and provide them with more profits, he said that following the GST reforms, the news coming from the market showed that farmers are buying tractors in large numbers during the festive season. “Because tractors have become even cheaper. When the Congress government was in power, everything was expensive for the farmers. Just look at tractors; the Congress government used to charge a tax of ₹ 70,000 on a tractor. After the new GST reforms, the same tractor has become cheaper by about ₹ 40,000,” he said.
India, EU may close trade deal this year
Following the 14th round of negotiations in Brussels, officials optimistic about finalising pact; while bilateral trade reached €120 billion in 2014, challenges remain over tariffs, sustainability, and carbon regulations; another round of talks is expected to be held in New Delhi in November
Indian and European Union officials remained confident that a trade deal between the two sides could be concluded by the end of the year, as the 14th round of negotiations drew to a close on Friday in Brussels.
“I can’t imagine a scenario where we’re not close to or have not concluded the FTA at the end of the year,” an EU official, who did not want to be named, told The Hindu.
Rajesh Agrawal, who has thus far led the negotiations with the U.S. and taken over as Commerce Secretary on October 1, was in Brussels this week, and left the city on Friday evening. The Hindu understands that with Mr. Agrawal’s appointment as Commerce Secretary, the Ministry’s Darpan Jain will lead India’s negotiations with the U.S., with Mr. Agrawal still having a very hands-on role in those talks.
The Indian negotiating team for the EU is led by L. Satya Srinivas. Another round of talks is expected in New Delhi in November but discussions will continue in the interregnum.
Bilateral trade in goods in 2024 stood at €120 billion ($139 billion) but difficulties remain and both sides complain of tariff and non-tariff barriers. Challenging areas have included services, agricultural and dairy sectors, pharma, automobiles, and wines and spirits. The sides have decided to set aside the most sensitive areas from the negotiations.
Political mandate
While officials are under a political mandate set by Prime Minister Narendra Modi and European Commission President Ursula von der Leyen in February this year to conclude an agreement by the end of 2025, some of these tough issues remain, including “trade and sustainable development”.
India has for long objected to the EU’s Carbon Border Adjustment Mechanism (CBAM). The tax, which seeks to price emissions released during the production of goods, including imports, is due to come into full effect on January 1, after a two-year transition period.
Commerce and Industry Minister Piyush Goyal has repeatedly said that India will retaliate if its products are subject to the mechanism. Mr. Goyal had warned, in a speech in New York at the end of September, that the CBAM “trap” could isolate Europe and cause inflation there. The government has also objected to bundling climate action with trade.
The issues around the CBAM and sustainability were very much still under discussion as of Friday afternoon, The Hindu learned from a source with direct knowledge of the negotiations.
The EU would need to adjust its approach on trade and sustainable development so the outcome is “something India can live with”, Chief Negotiator Christophe Kiener had told the European Parliament’s trade committee on September 25, saying a chapter on trade and sustainable development will still, however, be needed. Mr. Kiener had also said that while the sides had not made progress in the 13th round in New Delhi, they had improved their understanding of each other. Towards the end of such negotiations “things are bound to be difficult”, Mr. Kiener had said.
For the EU, India’s Quality Control Orders (QCOs) are among the oft-cited difficulties.
India’s Ambassador in Brussels, Saurabh Kumar, is optimistic about the trade talks.
“It is not a single point or one particular aspect that has overarching weight. Trade negotiations by definition are not easy and there are difficulties, but both sides are committed to it [the FTA] and determined to complete it,” Mr. Kumar told The Hindu, adding, “There is a strong political directive to complete discussions by December.”
Mr. Goyal is expected in Brussels at the end of the month.
IMEC ‘Sherpa’ meet
Brussels has been busy this week, with more than just trade. The Global Gateway Forum (the bloc’s strategy for investment in other jurisdictions) was also held this week along with a steering meeting (i.e., a ‘Sherpa’ meeting) for the India-Middle East-Europe Economic Corridor (IMEC). Deputy National Security Adviser Pavan Kapoor, who represented India at the meeting, participated virtually.
With a ceasefire kicking off between Israel and Gaza and the possibility of less fighting in the future, Brussels is keen on the project that was announced at the G-20 Summit in New Delhi in September 2023.
Key corridor
The corridor, when built, will provide transport, fibre optic and energy routes from India to Europe via West Asia.
“We are very keen on it, and the Indians are very keen on it, as are others. And we have these various investments we’re making to support legs of it. The key thing is the Middle East being sorted out,” the EU official said, adding that Washington’s attention to the issue was still necessary.
“We need the oomph of the Americans as well,” the official said.
Asked if there was any specific limiting factor to operationalise the IMEC project, Mr. Kumar said the countries involved in the project were now identifying their responsibilities.
“There is no limiting factor. The countries involved are trying to organise themselves as to how they are to move ahead and who looks after which aspect,” he said.
Centre asks States to adopt digital payments in schools
The Ministry of Education has written to States and Union Territories to adopt Unified Payments Interface (UPI), mobile payments, and Net banking for school-related financial transactions, the Centre said in a statement on Saturday. The Department of of School Education and Literacy sent this letter as part of its efforts to promote “Ease of living and schooling”. The Ministry cited “multiple advantages” of transitioning from cash to digital transactions, including convenience and transparency, the statement said. The government said the shift to digital payments would be an “important stride” in the government’s broader goal of digital transformation.
Overcoming U.S. tariffs, the U.P. way
Uttar Pradesh has introduced a range of financial schemes under the new Export Promotion Policy 2025–30 to support exporters impacted by tariffs and to strengthen their presence in new markets such as Europe and Asia; these schemes provide wider and more practical assistance than before
Uttar Pradesh has stepped up efforts to diversify its exports amid the challenge of the 50% U.S. tariffs that came into effect from August 27 this year. Our State’s key industries- carpets, leather, textiles, and handicrafts, form an important part of India’s $86.5 billion exports to the United States. We see this challenge as an opportunity to build a stronger and more resilient export base for Uttar Pradesh.
As Uttar Pradesh’s Minister for Export Promotion, I want to assure that the State is adopting a comprehensive and multi-pronged approach to support our exporters. Through initiatives like One District One Product (ODOP), we have been extending financial assistance and providing artisans and small businesses with the skills and tools to meet international standards, while also strengthening global connectivity so that our products can access newer markets. Also, at this crucial juncture, the Government of Uttar Pradesh has rolled out the Export Promotion Policy 2025–30, a landmark initiative that expands the scope of assistance and introduces new incentives, ensuring that our businesses are better equipped to withstand tariff pressures, diversify into alternative markets, and seize emerging opportunities across the world.
The recent U.S. tariffs have created difficulties for several export sectors of Uttar Pradesh. Leather factories have reduced production due to lower orders from the U.S., while Bhadohi’s carpet industry — contributing nearly 60% of India’s carpet exports to the U.S. — now faces about a 35% cost disadvantage compared with competitors such as Vietnam, which may affect employment. Gems, jewellery, and textiles are also likely to see an impact, with industry estimates suggesting a possible decline of over $4 billion.
These tariffs add to existing challenges such as higher shipping costs due to distance from ports, the need for greater skilling support for artisans to meet global standards, and U.P.’s current share of about 4.89% in India’s total exports (2024-25). While the situation is challenging, I want to assure our exporters and stakeholders that we are addressing these issues with practical and timely solutions.
Financial aid
Uttar Pradesh has introduced a range of financial schemes under the new Export Promotion Policy 2025–30 to support exporters impacted by tariffs and to strengthen their presence in new markets such as Europe and Asia. These schemes provide wider and more practical assistance than before, ensuring that both large and small exporters can compete globally.
Through the enhanced Marketing Development Assistance (MDA), exporters now get reimbursements at the rate of 75% across categories, with a cap of up to ₹25 lakh per exporter per year, including support for participation in international, domestic, and virtual trade fairs, as well as reimbursement for stall costs, airfare, publicity, certifications, and sending product samples. This will help our exporters showcase their products widely, build international networks, and diversify beyond the U.S. market.
Logistics support
As a landlocked State, U.P.’s exporters face higher transport costs to reach seaports. To ease this burden, the new policy provides 30% freight assistance up to ₹30 lakh per exporter annually, including air freight support up to ₹10 lakh. Special incentives have also been introduced for small exporters using LCL shipments, so they too can access global markets competitively. These steps will reduce logistics costs and help our exporters overcome the landlocked disadvantage.
To strengthen our exporters in the face of global challenges, the policy provides 30% reimbursement of ECGC premiums up to ₹5 lakh annually, a one-time 75% support on e-commerce onboarding fees capped at ₹3 lakh, and 75% reimbursement of postage charges through Dak Ghar Niryat Kendras up to ₹1 lakh per year. These measures reduce risks, cut costs, and open new global channels for Uttar Pradesh’s exporters.
To drive expansion and new investments, the policy introduces performance-linked rewards of 1% on year-on-year incremental export growth, up to ₹20 lakh annually per exporter. Further, new export-oriented projects will be supported with a capital subsidy of 40% of project cost, capped at ₹10 crore. These measures encourage both scaling of existing enterprises and the setting up of fresh, export-led industries in Uttar Pradesh.
Empowering artisans
Launched in 2018, the One District One Product (ODOP) scheme has become a strong driver of growth by promoting the unique products of all 75 districts of Uttar Pradesh—be it Banarasi sarees or Moradabad brassware.
Through skilling and provision of modern tools, the scheme ensures that our artisans produce quality goods aligned with international standards. In FY 2024-25 alone, 1,829 projects worth ₹1.06 crore were approved under ODOP. This initiative is not only enhancing production standards but also helping our artisans tap into emerging markets like Southeast Asia, Europe etc. Complementing this, the new U.P. MSME Audyogik Aasthan Prabandhan Policy offers further relief to the MSME sector. Nearly 700 acres are being developed as MSME parks, with land allotment to be facilitated through the GeM portal at a reserve price of ₹2,500 per sq. metre in central U.P. and ₹2,000 per sq. metre in the Bundelkhand region.
Building connections
The government under Chief Minister Yogi Adityanath, with the guidance of Prime Minister Narendra Modi, is committed to creating world-class infrastructure that makes exports seamless and cost-effective. Uttar Pradesh today has four international airports and nine domestic airports, with the upcoming Jewar airport poised to be a game-changer. Once operational, it will have an initial cargo capacity of 1 lakh tonnes.
At the same time, platforms like the Uttar Pradesh International Trade Show (UPITS) are strengthening our exporters’ linkages with global buyers.
$1-trillion goal
Through financial assistance, the ODOP initiative, improved connectivity, and focused skilling of artisans, we are strengthening the backbone of our export ecosystem. The recently launched U.P. Export Promotion Policy 2025–30, along with dedicated policies for footwear, leather, non-leather, and MSMEs, is attracting foreign investment and giving industries confidence to expand. These efforts not only create jobs and boost foreign exchange earnings but also pave way for U.P.’s $1 trillion economy vision.
Why did MOFs pioneers win the chemistry Nobel?
How are metal-organic frameworks being put to use across different applications? Why are they significant?
An MOF called CALF-20 can efficiently capture carbon dioxide from factory exhaust and is already being tested in industrial plants
For centuries, chemistry’s main terrain was to craft ever more complex molecules but it soon became clear to scientists that they were all confined to their own boundaries. The Nobel Prize in Chemistry 2025 honours three scientists who expanded that horizon. Susumu Kitagawa, Richard Robson, and Omar Yaghi have been feted for developing metal-organic frameworks (MOFs), little molecular scaffolds with vast internal spaces where other atoms and molecules can move, react or stay.
What is an MOF?
MOFs are crystalline structures in which metal ions serve as nodes and organic molecules as connectors. The resulting structure can have enormous internal surface areas — thousands of square metres per gram — and their pores can be customised to attract or hold specific molecules. By carefully choosing the building blocks, researchers can control the size and shape of the cavities and the chemical environment within. MOFs are thus among the most versatile materials ever created.
What did Robson and Kitagawa achieve?
In the 1970s, Richard Robson at the University of Melbourne was preparing ball-and-stick models to show students how atoms connect. He realised that the positions of the holes drilled into each atom contained all the information needed to determine the molecule’s shape. If that logic worked for small molecules, he wondered if it could be scaled up.
A decade later, Robson combined copper ions, which like to bond in a tetrahedral arrangement, with an organic molecule bearing four arms ending in nitrile groups. To everyone’s surprise, instead of a messy tangle, the components self-assembled into a diamond-like crystal. This lattice wasn’t dense like a diamond but full of empty cavities, each capable of hosting other molecules. Robson predicted that such “frameworks” could be tailored to trap ions, catalyse reactions, and sieve molecules by size.
However, Robson’s early crystals were fragile. Susumu Kitagawa in Japan made them stable and functional. Guided by his philosophy of finding “usefulness in the useless”, Kitagawa pursued porous materials even when they seemed too delicate to matter. In 1997, he used cobalt, nickel or zinc ions linked by a bridging molecule called 4,4’-bipyridine to build a true three-dimensional MOF. When the material was dried and refilled, gases such as methane, nitrogen, and oxygen could flow in and out without damaging the structure.
Kitagawa also recognised that MOFs could be soft rather than rigid, with flexible molecular joints allowing them to expand, contract or bend around depending on temperature, pressure, and the molecules inside.
What was Yaghi’s contribution?
Omar Yaghi in the U.S. gave MOFs their structural strength and reproducibility. Having grown up in modest circumstances in Jordan, Yaghi was fascinated by chemistry’s ability to create new forms of order. At Arizona State University in the 1990s, he sought a way to build extended materials by design, not by chance, using metal ions as joints and organic molecules as struts. In 1995, he made the first two-dimensional frameworks linked by cobalt or copper ions that could host other molecules without collapsing. Four years later, he achieved a landmark with MOF-5, a robust three-dimensional lattice made from zinc ions and benzene-dicarboxylate linkers. MOF-5 was strong and, notably, just a few grams had an internal surface area comparable to a football field. It was also intact when heated to 300°C and emptied of all ‘guest’ molecules.
By the early 2000s, his team had built entire families of MOFs with the same underlying geometry but different pore sizes and functions.
Why are MOFs important?
Chemists can easily make use of them for different applications. An MOF called CALF-20 can efficiently capture carbon dioxide from factory exhaust and is already being tested in industrial plants. MOF-303 can harvest drinking water from arid desert air by absorbing vapour at night and releasing it in sunlight. UiO-67 can remove persistent forever chemicals (PFAS) from water. MIL-101 and ZIF-8 can speed up the breakdown of pollutants and recover rare-earth metals from wastewater.
In the energy sector, NU-1501 and MOF-177 can store hydrogen or methane safely at moderate pressure, a crucial step toward clean-fuel vehicles. Others serve as containers for toxic gases in semiconductor manufacturing and as drug-delivery capsules that release medicines in response to biological cues.
How is the immune system kept in check?
What did the three Medicine Nobel awardees discover and why is it important? How do regulatory T cells function? How does their work on regulatory T cells lay the ground for a new field of research leading to new treatments for cancer and autoimmune diseases?
The Nobel Prize season for 2025 began with the announcement of the Physiology or Medicine Prize on October 6. The three awardees — U.S.-based researchers, Mary E. Brunkow and Fred Ramsdell, and Japan’s Shimon Sakaguchi — were chosen for their “discoveries concerning peripheral immune tolerance.” Their discovery enabled a fundamental understanding of how the immune system works — how it is regulated and kept in check. This has led to the evolution of several new potential treatment options, currently being tested, including for cancer.
What does their discovery mean?
Unless the body’s immune system is kept in check, it can attack its own organs. In that case, why do most people not develop autoimmune conditions where the body turns on itself? U.S. and Japanese scientists, working independently, arrived at an explanation for how the immune system is kept in check. It is for their work in making discoveries concerning what prevents the immune system from attacking the body that the Nobel was awarded. The laureates identified the immune system’s regulatory T cells which perform the precise task of preventing immune cells from launching an attack on the body.
Literally every day the immune system, a formidable army, is on guard, battling pathogens that try to invade the body. The question here is how do these cells “know what they should attack and what they should defend”, as the Nobel Committee pointed out. “Their discoveries have been decisive for our understanding of how the immune system functions and why we do not all develop serious autoimmune diseases,” said Olle Kämpe, chair of the Nobel Committee.
What are regulatory T cells?
The story goes back to Sakaguchi when he was working at the Aichi Cancer Centre Research Institute, Japan, some four decades ago. All T cells have special proteins called T-cell receptors on their surface. These receptors can be likened to a type of sensor. Using them, T cells can scan other cells to discover whether the body is under attack. There are a vast number of T cells with different receptors that can detect invaders, including new viruses. But they also have receptors that can attach to human tissues. But then, intuitively, is there a switch mechanism that warns the T cells off body cells?
In the 1980s, scientists realised that when T cells mature in the thymus, a small gland located in the upper chest behind the breastbone and in front of the heart that plays a crucial role in the immune system, they are taught to recognise and eliminate the body’s own proteins in a process called central tolerance. By the time Sakaguchi began his research into trying to understand this mechanism, his colleagues had already reportedly performed an experiment on newborn mice. They hypothesised that the mice would develop fewer T cells and have a weaker immune system if they removed the thymus. Instead, the immune system went into overdrive and ran amok, with the little mice developing several autoimmune conditions. This experiment might not have satisfied its primary goal, but in it was the idea for a Nobel that would come about 30 years later. Sakaguchi took off from where the experiment stopped. He injected these mice with T cells and it appeared that the T cells could protect the mice from autoimmune diseases.
Veering off from the current scientific wisdom of the time, Sakaguchi was convinced that the immune system must have some form of security guard — one that calms down T cells and keeps them in check; in this case, protecting the mice from the autoimmune condition. It took him over a decade, but in 1995, he presented to the world, a new class of T cells to the world, those that carried an extra protein called CD25 on their surface. This was called the regulatory T cell. But other researchers were not convinced yet of this idea.
It would take a second act, and efforts from Brunkow and Ramsdell, to concretely prove the experiment. A new set of mice, being studied since the Manhattan Project in fact, stood up to the occasion. In this instance, half of all the male mice were sickly and died in a few weeks, while the females thrived. It turned out the male’s organs were being attacked by T cells that destroyed the tissues. The Nobel-winning pair, who were then working at a biotech company Celltech Chiroscience in the U.S., realised that the mice could provide important clues in their work. After years of study, at an age when molecular biology was at best infantile, with a great deal of patience, they narrowed down on the faulty, mutant gene and named it Foxp3. They finally had an explanation for why a specific mouse strain was particularly vulnerable to autoimmune diseases. They also showed that mutations in the human equivalent of this gene cause a serious autoimmune disease, IPEX.
Two years later, Sakaguchi and others could prove, this time, convincingly, that the Foxp3 gene controls the development of the regulatory T cells, being able to prevent other T cells from mistakenly attacking the body’s own tissue, in a process that is called peripheral immune tolerance. Regulatory T cells also ensure that the immune system calms down after it has attacked invaders, answering Sakaguchi’s initial question.
What are the specific uses in medicine?
While specific therapies are yet to hit the market, over 200 studies involving regulatory T cells are currently in progress, said Thomas Perlmann, secretary-general of the Nobel Assembly, while making the announcement of the prize on October 6. These stand testimony to the potential slew of new treatment modalities to address various conditions.
This includes work on cancer — dismantling the regulatory T cells so that the immune system can access the tumours and set to work on them; and on autoimmune disorders where researchers are trying to promote the growth of more regulatory T cells, inside the body, but also outside of it, in order to make sure that the immune system does not attack its own body.
It is also believed that this research will have far-reaching implications for organ transplantation by regulating organ acceptance. Clinical studies are afoot to test many of these pathbreaking treatment modalities.
What is macroscopic quantum tunnelling?
What did the three physics Nobel laureates conduct research on? How will their findings open the door to emerging technologies used to collect information? What can a circuit with a Josephson junction mimic? How will it help superconducting quantum processors?
Particles can sometimes cross barriers they don’t have the energy to climb, like boring through a mountain instead of scaling it first, as per quantum mechanics. This process, called tunnelling, is common in nuclear and atomic physics. The 2025 physics Nobel Prize laureates John Clarke, Michel Devoret, and John Martinis showed that such behaviour can occur not only in subatomic particles but also in an electrical circuit made of superconductors.
What is a Josephson junction?
The fundamental unit of the award-winning experiments the trio conducted is a device called a Josephson junction. Here, two superconductors are separated by a very thin insulator. The trio wanted to know if a parameter of the circuit as a whole, in this case the junction’s phase difference, could behave like a single quantum particle. They came away from their experiments with a resounding ‘yes’, by observing both macroscopic quantum mechanical tunnelling and discrete energy levels in the circuit. In a superconductor, many electrons pair up and move without resistance. In a Josephson junction, the phase difference between the two superconductors measures how out of step the collective quantum wave of paired electrons is on one side compared with the other. This phase’s value controls how easily the pairs can cross the insulating barrier. When this phase becomes trapped in an ‘energy valley’, quantum mechanics allows it to tunnel through to the other side, producing a small but measurable voltage across the junction.
When the scientists sent a current through the Josephson junction, they found that if it was small enough, the flow of paired electrons was stalled by the insulator and the circuit produced no voltage. In classical physics, this state would never change: the electrons’ flow would remain blocked. But in the quantum world, the current has a small chance of suddenly tunnelling through the insulator and flowing freely on the other side, creating that voltage.
Why was the circuit fragile?
In the early 1980s, several groups searched for this tunnelling by varying the current and recording the value at which the junction produced a voltage. If the electron pairs were simply escaping to the other side due to thermal fluctuations — akin to being heated enough to jump across the mountain — cooling the device ought to steadily increase the amount of current required to produce a voltage. On the other hand, if the electron pairs were tunnelling through, the rate of crossing over would eventually stop changing with temperature. Simple though the setup was, the challenge was in keeping stray microwave radiation from affecting the circuit and producing data consistent with the temperature-independent behaviour. So the experimenters needed to reduce and characterise environmental noise with great care.
The team led by Clarke, working with Devoret and Martinis, solved this problem by redesigning their setup so stray signals couldn’t interfere. They used special filters and shielding to block unwanted microwaves and kept every part of the experiment extremely cold and stable. Then they sent in faint yet precisely tuned microwave pulses to gently test how the circuit responded, allowing them to measure its electrical properties accurately. When they finally cooled the system to very low temperatures, they saw that its behaviour matched the exact patterns predicted by quantum tunnelling theory.
How did the circuit show quantum effects?
The researchers also wanted to find out if the circuit’s trapped state behaved like a quantum system with distinct energy steps — a hallmark of a quantum state — instead of a smooth range. They shone microwaves of different frequencies onto the junction while adjusting the current. When the frequency exactly matched the gap between two allowed energy levels, the circuit suddenly escaped more easily from its trapped state. The higher the level, the faster this escape happened. These patterns showed that the circuit’s overall state could only receive or emit fixed packets of energy, which is also how a single particle following the rules of quantum mechanics would behave. In short, the circuit as a whole behaved like a quantum particle.
Put together, the results revealed two facts. First, a macroscopic electrical circuit — one that you could see with the naked eye — could display quantum behaviour when sufficiently isolated from its environment. Second, a relevant macroscopic variable in that circuit could be understood using the standard tools of quantum mechanics. These experiments also pointed to a practical path for controlling and ‘reading’ macroscopic quantum states — in this case using a bias current, weak microwaves, and sufficient protections to shield from external radiation — one that gave the field a template to make reliable quantum measurements in solid-state devices. Subsequent work extended these ideas, developing superconducting qubits, embedding them in microwave resonators, and improving their coherence.
What are the applications of this work?
The technological applications flow from the same physics. A circuit with a Josephson junction can be made to mimic the quantised energy levels of an atom; microwaves could drive the circuit to jump between these energy levels; and carefully coupling the circuit to a resonator could allow an operator to measure changes in the circuit without disturbing it. This architecture, known as circuit quantum electrodynamics, is the foundation of many of today’s superconducting quantum processors (The resonator is like an echo chamber for microwaves. When the circuit is coupled to a resonator, the two can exchange energy in a controlled way, allowing scientists to measure the circuit’s state indirectly by observing changes in the resonator’s behaviour).
Superconducting circuits that exploit macroscopic quantum effects are central to several emerging technologies. They are quantum amplifiers that boost extremely weak signals without adding noise — a useful ability in diagnostics as much as searches for dark matter. They are used to measure current and voltage with extraordinary precision. They can be microwave-to-optical converters that link quantum processors to fibre-optic networks. They are components in quantum simulators used to model complex materials or even chemical reactions atom by atom.
