In the wake of World War I, relations between mathematicians who had been on opposite sides of the conflict were shaky at best. After the International Mathematical Union (IMU) was held the International Congress of Mathematicians (ICM) in Bologna, Italy, in 1928, Canadian mathematician John Charles Fields proposed conferring a medal at ICM as a way to help reconcile divisions among IMU members. Fields traveled to Europe to seek approval for the award from various mathematical organizations in different countries before it was formally adopted by the union in 1936 and named after him posthumously.

The creation of the Fields Medal helped to mend fences among European mathematicians nearly 100 years ago and continues to highlight mathematical excellence and global collaboration — the latter of which is being tested with ICM 2026. Held every four years, the congress is set to take place in Philadelphia this summer, but a movement within the math community to move the congress out of the United States is gaining ground. An article published in Scientific American at the end of March spotlighted how recent controversy surrounding U.S. immigration and visa policies has inspired mathematicians around the world to sign a petition to relocate ICM 2026, scheduled for July 23-30 at the Pennsylvania Convention Center, to a “neutral” country.

The petition lays out a number of reasons why IMU members oppose holding this year’s congress in the United States, including serious doubts about delegates’ safety while in transit: “The current American government has demonstrated in no uncertain terms its unbridled hatred of immigrants. This stance has increased the risks of traveling to the US, as it is now a country on the verge of martial law and there is a serious concern that academics (or anyone) traveling to the US may be denied entry. Indeed, the French mathematical society has already chosen not to attend the conference for these very reasons.“

“Holding the ICM in the United States, after it started two illegal wars, represents a double standard, given that, practically immediately after Russia invaded Ukraine, the ICM in Russia was canceled,” Michael Harris, a Columbia University math professor, told The Guardian. He is one of 69 current and past ICM speakers who have joined the movement to relocate this year’s conference. At the time of writing, 2,403 mathematicians from 76 countries had signed the petition.

On February 24 — about 10 days after the launch of the petition — the ICM 2026 local organizing committee released a statement online confirming that ICM 2026 would be held in the United States as planned and laying out the rationale for the decision:

In recent months, some members of our community have expressed concerns regarding the safety and well-being of participants in the context of today’s politically fractured climate. We take these concerns seriously. The Organizing Committee is fully committed to providing a safe, welcoming, and respectful environment for all attendees. The ICM is an academic gathering devoted to mathematics—its ideas, its practitioners, and its global community—where participation is centered on scholarly exchange. We are working closely with local partners to ensure that the Congress proceeds as planned and that participants can focus fully on the scientific and communal goals of the meeting.

Beyond these practical considerations, we wish to emphasize the deeper purpose and spirit of the ICM. For more than a century, the Congress has existed to honor mathematicians from all parts of the world and to bring together our community across borders, cultures, nationalities, and ethnicities. This commitment to internationalism and mutual respect is not incidental; it is central to who we are as mathematicians and to how mathematical progress is made.

At moments when political forces threaten to fragment the international scientific community, the ICM stands for the opposite principle: openness, solidarity, and shared intellectual purpose. Gathering in Philadelphia is not only an academic act, but also an affirmation that mathematics transcends political divisions and that our community remains united in its values. We believe strongly that engagement, presence, and dialogue are essential to upholding the ideals that the ICM represents.

We therefore encourage mathematicians from the United States and from around the world to attend the ICM. Your participation honors our colleagues globally, strengthens our shared institutions, and affirms our collective commitment to an open and inclusive mathematical community. Standing together—calmly, peacefully, and resolutely—is the most effective way to preserve the unity and international character of our field.

Convene reached out to both the local organizing committee for ICM 2026 and the leaders behind the petition to move the meeting out of the United States to better understand both sides and how the controversy will directly impact the congress.

‘Opportunities for Interaction and Expressing Actual Agency Over the Course of the Mathematical Community’

Jalal Shatah, a mathematics professor at New York University and the head of the ICM 2026 local organizing committee, emphasized that holding the meeting in Philadelphia as planned was not an easy decision. “We are very aware that some colleagues have concerns about travel, safety, visas, and the broader political climate. Those concerns are real, and we have taken them seriously from the beginning,” he said. “The ICM is the central gathering of the international mathematical community. It is not only a conference of lectures; it is where mathematicians from across fields, generations, and countries come together, where major achievements are recognized, where young mathematicians encounter new ideas, and where collaborations are born.” He noted that it has been eight years since ICM members have met in person, which made “preserving that opportunity for the global community … extremely important.”

That belief that an in-person gathering is critical is held by both the organizing committee and the petitioners and used as justification for each group’s stand. Tarik Aougab, an associate professor of mathematics at Haverford College who organized the petition along with Ila Varma, an associate professor of mathematics at the University of Toronto, told Convene, “Math is a very global community, so we all know people who are not able to come to ICM 2026 for either safety reasons or else not having access to a visa to actually travel to the U.S.”

The ICM 2026 local organizing committee shared that they plan to augment ICM 2026’s online footprint to help accommodate those who won’t be there in person. “The congress will have a broader access component: sessions will be recorded and made available online after a short editing process. This is not a replacement for the in-person ICM, but it is an important way to make sure that the mathematics reaches colleagues who may not be able to attend,” Shatah said. “The goal is to preserve what makes the ICM special as a gathering of the world mathematical community, while also making the mathematics available to colleagues who cannot be there.”

Near-instantaneous access to session content is a step in the right direction for providing equal access, but it does not translate to true equity for the international math community, Aougab told Convene. “This is the biggest math conference in the world, and unlike lots of other conferences, it has a genuinely participatory dimension. There are resolutions that get voted on at a conference like this, and there are all sorts of opportunities for interaction and expressing actual agency over the course of the mathematical community — and that’s the exact part of the conference that somebody

The hybrid concession does not represent equal access for all, a principle Aougab stands behind. “It’s my belief that access to this kind of scientific knowledge is a human right, and so even if making the conference accessible to the largest portion of people had absolutely no impact on the health of mathematics as a science, it would still be a matter of moral importance to open it up to the largest population of people,” Aougab said, “solely because everyone deserves that access.”

‘When I Found Out That the ICM Was Going to Be in the US, I Already Knew I Wouldn’t Be Able to Go’

Aougab’s frustration and sense of solidarity with mathematicians who cannot travel to the United States for the congress are echoed in the anonymized comments from signatories that he and Varma have published on the ICM out of USA website where the petition is hosted:

“I have been selected to participate in the congress, but my country is on the list of countries whose citizens are not eligible for a visa. This puts me at a disadvantage.”

“As a young Cuban mathematician, when I found out that the ICM was going to be in the US, I already knew I wouldn’t be able to go.”

“I was awarded an important financial grant to participate to ICM 2026 by a short communication (it was already accepted) if I get a visa, which is difficult as I am Tunisian.”

“I regret to inform you that my U.S. visa application was denied at the U.S. Consulate in Lagos (Victoria Island) on April 22, 2026. The decision was due to an alleged current US government visa restriction affecting Nigerian visa applicants which came into effect on January 1, 2026. This was despite my submission of all required documents, including the official ICM invitation letter.”

Other mathematicians who signed the petition were moved by principle rather than potential danger or difficulty in traveling to Philadelphia this summer.

“The comments of the IMU in 2022, announcing the move of the ICM from St. Petersburg to online, should be deeply considered. What are the differences between the decision then, and the high-minded comments about internationalism and transcending political divisions now? I do not wish to participate in the hypocrisy.”

“I originally wasn’t going to sign … The B1 Bridge bombing, and the US president celebrating this apparent war crime targeting civilian infrastructure, was … too far for me. The Trump administration needs to experience some pressure for its lawless behavior.”

“In solidarity with mathematicians of the Global South, the IMU’s legitimacy to society beyond the mathematics field is at stake. In respect for the imperative role and contributions of mathematicians residing outside the US and who are advancing the field from the margins of the Western world, the IMU must reject the United States as a viable host for the ICM or else risk backsliding into the same decay the world is currently witnessing in the US empire.”

It’s worth noting that opposition to hosting ICM 2026 in the U.S. is not limited to the launch of the petition in February. More than a year before the petition was launched, Peter Woit, a senior lecturer in the math department at Columbia University, wrote a post on his site Not Even Wrong registering concern about hosting the meeting in Philadelphia as planned: “Given how fast things are evolving, it’s impossible to predict what the situation will be in July 2026. The ICM 2022 debacle was caused by the decision to hold the ICM in a country governed by a dangerous dictator, then hope for the best and not make contingency plans. The same mistake should not be made twice.”

Notices of the American Mathematical Society also published a letter to the editor from Ghent University Professor of Mathematics Hendrik De Bie expressing his grave concerns about how holding ICM 2026 in the United States could tarnish the entire field in its April 2026 issue. “The safety of international but equally of American participants (especially when non-white or members of a minority) seems very tenuous at this point. It is my view that holding the most important conference in a field of science (here: mathematics) there right now is not a good idea. Doing so will tarnish the public image of the field, keeping in mind also the major press attention the award ceremony of the Fields Medals receives.”

‘Practical and Constructive’ Considerations

The decision to stick to the established plan is rooted in logistics more than politics, Shatah acknowledged. “From the perspective of the local organizing committee, our responsibility is practical and constructive,” he said. “An event of this scale cannot simply be moved a few months before it takes place. The scientific program, the invited speakers, the travel grants, the venue, the public events, the local partnerships, and the participation of thousands of mathematicians have all been built around Philadelphia. Our responsibility, therefore, is to make the congress work as well as possible: safely, professionally, and inclusively.”

Shatah also spoke about how the destination has shaped ICM 2026’s themes and programming. “Philadelphia in 2026 is a meaningful setting. The city will be marking the 250th anniversary of the United States, and we hope the congress can reflect some of the best ideals associated with that history: openness, tolerance, civic life, and the welcoming of people from around the world. The ICM will also be part of a larger celebration of mathematics, with public events, cultural activities, and outreach beyond the research community. So the reasoning was not simply ‘continue as planned,’ it was continue with seriousness, with care, and with a renewed commitment to the international mathematical community. We want ICM 2026 to be scientifically outstanding, welcoming to participants, and faithful to the idea that mathematics transcends national, political, and cultural divisions.”

It remains to be seen how many delegates will choose to travel to Philadelphia for ICM 2026 this summer. At the time of writing — less than 90 days before the meeting kicks off — petition signatures are trending ahead of meeting registrations.

‘A Different Set of Concerns’

Although a last-minute change of location for a major international meeting is never practical, it isn’t unprecedented for IMU. ICM 2022 was slated to be held in St. Petersburg, Russia in July before Russia’s invasion of Ukraine on Feb. 24, 2022 turned that plan on its head.

Shatah sees the current state of affairs in the United States as markedly different than Russia in 2022. “The 2026 context raises a different set of concerns, and we do not dismiss them. The U.S.-Iran conflict has created anxiety, especially for colleagues from the region and for those who may face visa or travel uncertainty. But operationally it is not the same situation as 2022. Philadelphia is not in the war zone. The United States remains reachable through the normal international aviation network. There may be disruptions affecting parts of the Middle East, including airspace closures and rerouting, but those are not the same as the breakdown of the host-country travel environment that the IMU confronted with St. Petersburg. Current travel complications are concentrated around Iran and parts of the region, whereas ICM 2026 is being held in Philadelphia, a major international convention city.”

Although Shatah is correct to point to travel disruptions caused by the onset of the Russia-Ukraine conflict, he fails to address potential attendees’ concerns about human rights violations tied to recent U.S. foreign policy. A statement from the Berlin–based IMU executive committee on March 30, 2026 about the fog of doubt surrounding ICM 2026 echoed the sentiments of the local organizing committee and entirely sidestepped the humanitarian issues raised by signatories to the petition: “Promoting international exchange is at the core of the IMU’s mission. At a time when international collaboration and science face serious challenges, we strongly believe that holding the ICM in person in Philadelphia is especially important. We understand the concerns about entering the United States, as well as about feeling safe and welcome in Philadelphia and at the Congress. The local organizing committee is fully committed to providing a safe and welcoming environment for all participants and has recently made additional arrangements to help mitigate risk.”

By contrast, the executive committee for ICM 2022 was far more vocal in calling out humanitarian issues tied to the Russia-Ukraine conflict as a key factor in moving the meeting online, as laid out in a statement made on Feb. 22, 2022:

The IMU GA is the highest body of the IMU, and at the GA important decisions for the IMU are taken for the coming four years, including elections and budgets. However, recent developments in Russia and Ukraine have changed the situation dramatically.

The actions of Russia have been condemned worldwide, and have made an in-person event in Russia impossible. Indeed, the Secretary General of the UN issued the following appeal directly to the Russian government on 23 Feb. 2022 «In the name of humanity bring your troops back to Russia. In the name of humanity do not allow to start in Europe what could be the worst war since the beginning of the century». This call has not been heeded.

We, the Executive Committee of the IMU, have analyzed the situation carefully. We strongly condemn the actions by Russia. Our deepest sympathy goes to our Ukrainian colleagues and the Ukrainian people.

It’s not fair to make a direct comparison between St. Petersburg in 2022 and Philadelphia in 2026, but in both instances people in the math community speaking up about attendee safety, travel disruptions, and potential moral injury have been heard quite differently. “I think when mathematicians are at our best, which is not always, we have a pretty hard time dealing with contradiction,” Aougab said. “And so when we see this sort of double standard playing out in real time, and with actual lives hanging in the balance, that’s the kind of hypocrisy that is going to make the hairs on the back of a mathematician’s neck stand up.”

There will likely be no further response from IMU or the local organizing committee to the petition to move ICM 2026, but Aougab and his fellow mathematicians haven’t given up the fight. “We held a virtual round-table for signatories earlier in the week and all I can say right now is that many people from all over the world are very invested in having the conference moved out of the United States,” he said when Convene followed up with him on Apr. 29.

The mathematicians who have come together to take a stand against discriminatory visa practices and U.S. aggression on the world stage are may not be in Philadelphia this summer to see the Fields Medal presented, but their commitment to equity and justice echoes the ethos that J.C. Fields laid out in the letter that he sent to European mathematicians almost a hundred years ago: “The above program [to designate how recipients will be chosen and the award presented] means a new departure in the matter of international scientific cooperation and is likely to be the precursor of moves along like lines in other sciences than mathematics. One would hear again emphasized the fact that the medals should be of a character as purely international and impersonal as possible. There should not be attached to them in any way the name of any country, institution, or person.”

Kate Mulcrone is Convene’s digital managing editor