Most scientists, once they had delved deeply into the cosmological mysteries of our universe, would be satisfied. Where else is there to go once you’ve ranged from quantum coherence in neurons to the “Ultimate Ensemble Theory of Everything,” as the Swedish-born MIT physicist and cosmologist Max Tegmark has over the course of his career?

But Tegmark isn’t just concerned with the physical and mathematical structure of our world. He’s worried about whether it has a future at all.

Increasingly concerned about the growing threat from advanced artificial intelligence — a subject he covered in his highly readable (for a physics professor) book Life 3.0: Being Human in the Age of Artificial Intelligence — Tegmark in 2014 co-founded the Future of Life Institute (FLI), a nonprofit organization in Cambridge, Massachusetts, that focuses on reducing catastrophic and existential threats from technology. As Tegmark wrote at the launch of FLI, “The coming decades promise dramatic progress in technologies from synthetic biology to artificial intelligence, with both great benefits and great risks.” FLI’s mission would be to ensure that the promise would outweigh the threat.

In creating FLI, Tegmark joined a host of other institutions — such as Oxford’s Future of Humanity Institute and Cambridge’s Centre for the Study of Existential Risk — that arose in recent years to put both a scholarly and an activist lens on the rising danger of existential catastrophes.

But FLI forged a somewhat different path. It was US-based in a field that had begun in the UK, and was adjacent to both MIT and Harvard, giving it a close view on cutting-edge research in both artificial intelligence and synthetic biology, the nascent science of writing and rewriting the code of life.

FLI has also not been shy about the danger of “autonomous weapons” — AI-controlled armaments that represented what some theorists have called the third revolution in warfare, after gunpowder and nuclear weapons. With a savvy sense for media, the group released a pair of faux-documentary, quite scary videos — one in 2017 and one in 2021 — about the coming dangers of “slaughterbots,” robot weapons programmed to kill. Tegmark identified the unique dangers of such weapons, which could lower the barrier to using force precisely because “they’re so small and cheap that they can proliferate,” he told me in 2021.

But if Tegmark often looks to the threats of the future, he also keeps one eye on the past. From its founding, FLI has been loud about the dangers of nuclear war, an attitude that now seems prophetic as the actual use of nuclear weapons seems more possible than it has in decades. Beginning in 2017, FLI has handed out an annual “Future of Life” award, for the person who had done the most to improve the present, by preventing global catastrophe in the past. The first winner in 2017 was Vasili Arkhipov, a Soviet naval officer who during the Cuban missile crisis in 1962 prevented his sub from launching a nuclear warhead at blockading American ships, thus plausibly preventing what could have become World War III.

At the ceremony for Arkhipov, who died in 1998 with little recognition for his heroism, Tegmark said that he was “arguably the most important person in modern history” for his actions preventing a nuclear holocaust. Whether Tegmark himself will make a similar deep mark on history remains to be seen, but he won’t stop ringing the alarm bell.