Generated by Codex with GPT 5.6 Sol XHigh

The search for nature’s deepest laws usually sounds remote from ordinary politics. In this interview, Nobel Prize-winning physicist David J. Gross argues that the two cannot be separated: a final theory may take centuries to discover and confirm, while nuclear war could end the civilization capable of finding it in an afternoon. Protecting humanity’s scientific future, in his view, therefore belongs alongside the scientific work itself.

From a proven breakthrough to an unfinished theory

Gross helped make one of the decisive advances behind the Standard Model of particle physics. In the early 1970s he co-discovered asymptotic freedom, the counterintuitive behavior of the strong nuclear force in which quarks interact more weakly at extremely short distances but resist increasingly strongly when pulled apart. That insight helped establish quantum chromodynamics, or QCD, and earned Gross a share of the 2004 Nobel Prize in Physics.

His later work moved into less certain territory. Gross helped formulate heterotic string theory, a mathematically elegant attempt to describe fundamental particles and bring gravity into a framework with electromagnetism and the strong and weak nuclear forces. Unlike QCD, however, string theory has not received experimental confirmation. Gross presents that contrast as characteristic of modern fundamental physics: theory has become richer just as decisive new data have become harder to obtain.

The difficulty is not simply that experiments are more expensive. Physics advances toward smaller distances by reaching higher energies, and the next theoretically meaningful scale may lie roughly 20 orders of magnitude beyond what current machines can readily probe. Gross says the scientific payoff changes only logarithmically as researchers move to shorter distances, while accelerator costs rise at least with the square of the energy. Better technology can help, but it does not erase that widening mismatch. Experiments that once tested predictions within a year are now planned on horizons of 30 to 60 years.

The shorter horizon

Gross is using his \$3-million Special Breakthrough Prize in Fundamental Physics partly to support research institutes and partly to amplify nuclear-risk advocacy. He is helping revive the Mainau process through the Nobel Laureate Assembly for the Prevention of Nuclear War, a group seeking renewed international attention to arms control and nonproliferation.

His warning rests on the way a small annual risk compounds. Gross cites older estimates of a 1 percent yearly chance of nuclear war and personally argues that the present risk may be 2 percent, given weakened arms-control arrangements, proliferation and conflict involving nuclear powers. He translates those figures into dramatically shortened expected lifetimes for people born today. These numbers are an illustrative risk argument, not a precise forecast: they depend on uncertain annual probabilities and on the severe assumption that a nuclear war would be fatal to the people whose lifetimes are being estimated. Their purpose is to make an abstract recurring danger feel cumulative rather than negligible.

The most important point, Gross says, is that lowering the risk does not require instant worldwide disarmament. Even reducing the annual probability to a tenth of a percent could buy humanity centuries in which to address nuclear weapons and other threats. He wants scientists and young people in particular to rebuild the political pressure that earlier helped produce limits on atmospheric testing and nuclear arsenals.

He compares that task with climate advocacy. Decades of scientific warning made climate change a mainstream concern despite organized opposition, whereas awareness of nuclear danger faded after the Cold War even though the weapons remained. Nuclear war is also uniquely abrupt: climate change can cause immense and lasting harm, but a global thermonuclear exchange could destroy much of civilization within a day.

Defense, survival and scientific optimism

Gross rejects the idea that a technological shield such as the proposed Golden Dome missile-defense system can remove the danger. He sees it as a larger descendant of Ronald Reagan’s Strategic Defense Initiative. Offense has structural advantages: attackers can add warheads and decoys, while defenders must stop nearly everything, and a single weapon penetrating the shield could devastate a city. Missile defenses can also spur an expensive arms race and encourage the illusion that nuclear conflict is survivable.

Yet the interview does not end in fatalism. Gross is pessimistic about the present nuclear situation but insists that it is made and maintained by people, not imposed by nature. Public understanding and political action can change it. His broader optimism comes from physics itself. Frontier research demands faith that answers are reachable even when no one knows the mountain’s height. Looking forward can make progress seem painfully slow; looking back a decade often reveals how much understanding has changed.

The quest for a theory of everything thus has two frontiers. Physicists must keep climbing toward laws that unite the forces of nature, but society must also preserve the long future such a climb requires. Scientific ambition is meaningful only if humanity survives long enough to fulfill it.