One of the world’s biggest scientific conferences—the March Meeting of the American Physical Society (APS)—has been cancelled little more than a day before it was scheduled to begin in Denver, Colorado, for fear of contributing to the spread of coronavirus. Although many physicists have been left stranded by the unprecedented decision, some would-be attendees are finding ways to share their talks virtually.

“At first, it was just a shock,” says Nicholas Drachman, a graduate student who works on protein sequencing at Brown University in Providence, Rhode Island. “It was clear it wasn’t a joke, but it just seemed such late notice that we were all very surprised.” The week-long meeting is the biggest on the physics calendar, and more than 11,000 people had been registered to attend.

Drachman and hundreds of other registered participants had already arrived in Denver on 29 February, when they received an e-mail from the APS. The 2020 March Meeting was being called off “due to rapidly escalating health concerns relating to the spread of the coronavirus disease”, the communiqué said. “Please do not travel to Denver to attend the March Meeting.” The conference was scheduled to start 36 hours later, on 2 March.

“I understand the cancellation: having 11,000 people in one place is a risk,” says Toma Susi, another physicist who had arrived on 29 February. “What I question is, what has changed in the last 24 hours?” Susi, who manipulates single atoms with scanning transmission electron microscopy at the University of Vienna, was scheduled to give an invited talk about early-career grants disbursed by the European Research Council.

Because his hotel room was non-refundable and changing his flight would have been prohibitively expensive, Susi has decided to stay in Denver for the rest of the week. He says he will take advantage of the opportunity to network with colleagues, despite the cancellation. (On 1 March, some local bars were offering a free drink to stranded physicists.) But he feels that staying in Denver also carries some risks, as the coronavirus crisis evolves. The virus, which causes the disease COVID-19, has begun spreading rapidly in several places outside China in the past week, and national health systems are racing to contain escalating outbreaks. “One concern is that flight travel gets blocked completely,” he says.


Some researchers have found creative ways to get the word out about their research, despite the cancellation. Leigh Martin, who works on quantum-sensing technology at Harvard University in Cambridge, Massachusetts, plans to record a video of the talk he was due give in Denver. He will then upload it to, a website that another physicist quickly set up for this purpose. The APS itself says it will provide a platform for sharing presentations, and is asking registrants to submit links to their talks.

And at least one of the society’s divisions, for soft-matter research, has planned a series of web-streamed seminars matching its original talk schedule, to serve as a virtual conference.

“It was clear that nothing formal was possible, like recreating the whole meeting virtually”, so speakers were invited to post their own links to an online spreadsheet, says Karen Daniels, a physicist at North Carolina State University in Raleigh who is leading the effort. “This was all possible because there is a large enough Twitter presence among our membership to have gotten it started.” Several other APS divisions are considering similar initiatives, Daniels told Nature.

Daniels was able to cancel her own travel plans in time, but a number of participants in Denver are holding informal get-togethers within their disciplines, she says, a practice often referred to as unconferencing.

Independent decision

The APS leadership took its decision to cancel the conference independently, and had not communicated directly with US authorities such as the Center for Disease Control and Prevention (CDC), APS chief executive Kate Kirby said at a press conference on 1 March. “The decision was made just considering what we felt to be the risk,” she said.

A major factor, said Kirby, was the CDC’s decision on last week to upgrade Italy and South Korea to the highest level of travel warning, which includes a recommendation to avoid all non-essential trips. As a consequence, at least 500 participants were scheduled to arrive from countries that are now a “hotspot for contagion”, Kirby said—but she added that she did not know how many participants from ‘at risk’ countries had already flown to Denver. (Hundreds of participants from China had already cancelled their trips, the APS has said.) The society says it will refund registration fees to all paying participants.

And the APS is not alone: there are reports of several other scientific conferences being cancelled because of coronavirus disruption. These include a meeting this week of the European Society for Medical Oncology in Paris, and the European Lunar Symposium, planned for mid-May in Padua, Italy. The lunar meeting will now be an online-only conference.

Rather than hanging around in Denver, Martin cancelled his hotel and changed his flight to return home right away—although he’s heard that some attendees are taking advantage of the nearby Rocky Mountains. “Everyone else is either going skiing or going back home.”

This article is reproduced with permission and was first published on March 2 2020.

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