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John Baez (Dec 10 2025 at 15:54):This could be a reason not to hold conferences (like ACT) in the United States. From the Washington Post:
U.S. plans to ask visitors to disclose 5 years of social media history
The proposal would affect travelers from countries on the visa waiver program, including Australia, Britain, France, Germany, Israel, Japan and South Korea.
The United States could begin requiring visitors from countries on the visa waiver program to provide up to five years of their social media history, according to a U.S. Customs and Border Protection proposal posted to the Federal Register to be officially published Wednesday.
There are dozens of countries on the visa waiver program list, including many European nations, Australia, New Zealand, South Korea, Japan, Brunei, Singapore, Qatar, Israel and Chile.
The proposal suggests adding social media as a “mandatory data element” for an Electronic System for Travel Authorization (ESTA) application.
Applicants would also have to provide additional information “when feasible,” according to the proposal. The list includes telephone numbers used in the last five years, email addresses used in the last 10 years, IP addresses and metadata from electronically submitted photos, and biometrics, including facial, fingerprint, DNA and iris data.
It would also require applicants to provide information about their family members, including names, telephone numbers, dates of birth, places of birth and residences.
According to CBP, the proposal is open for a 60-day public comment period.
John Baez (Jan 11 2026 at 17:09):Is anyone here aware of efforts to move the ICM so that it doesn't take place in the US? Currently the International Congress of Mathematicians (ICM) is going to be held in Philadelphia, 23–30 July 2026. You'll recall that when Russia invaded Ukraine, the 2022 ICM was moved out of St. Petersburg after some heel dragging.
All I've seen about this is Peter Woit's column where he wrote:
In 2022 the St. Petersburg ICM was canceled due to the Russian military entering Ukraine and attempting to take over the country by force. The US has threatened to do the same thing to Greenland and to Panama. Will the Philadelphia ICM be canceled if this happens?
Morgan Rogers (he/him) (Jan 12 2026 at 09:11):Depends whom and where the organisers are, no doubt.
Cole Comfort (Jan 12 2026 at 14:07):Morgan Rogers (he/him) said:
Depends whom and where the organisers are, no doubt.
I would imagine that in general there are more influential people in the American sphere of influence, rather than the Russian sphere of influence. If you recall, LiCS was in Israel not too long ago, and there was not much pushback at all.
John Baez (Jan 13 2026 at 04:18):It may also depend on whether the US invades Greenland before July 23rd.
John Baez (Jan 26 2026 at 22:22):The French Mathematical Society is not coming to the International Conference of Mathematician in Philadelphia in 2026:
La SMF ne tiendra pas de stand au Congrès International des Mathématiciens (ICM) de Philadelphie en 2026.
(Motion du Conseil d'Administration du 16 janvier 2026)
En effet ni la délivrance de visas par le pays hôte, ni sa sécurité intérieure alors qu'y est régulièrement évoquée la loi martiale, ne semblent garanties.
Par ailleurs la SMF reste fondamentalement attachée à l'héritage de Benjamin Franklin, inséparable de la pensée rationnelle, et condamne la défiance envers la science et toute atteinte aux libertés académiques.
John Baez (Jan 26 2026 at 22:23):Or for those of us who can barely read French:
The French Mathematical Society (SMF) will not have a booth at the International Congress of Mathematicians (ICM) in Philadelphia in 2026.
(Motion of the Board of Directors, January 16, 2026)
Indeed, neither the issuance of visas by the host country nor its internal security, given the frequent discussions of martial law, seem guaranteed. Furthermore, the SMF remains fundamentally committed to the legacy of Benjamin Franklin, which is inseparable from rational thought, and condemns the distrust of science and any infringement on academic freedom.