Physics and Nuclear Disarmament

With the Russian invasion of Ukraine, the threat of nuclear weapons use has re-emerged in the public debate. Today, there exist over 12,000 nuclear weapons globally, and large fissile material stocks allowing the production of many more. While the war and the political climate will not allow disarmament initiatives in the foreseeable future, the public debate has triggered a new sense of urgency.

Physicists have an important role: To enable international agreements on warhead and fissile material reductions, strong verification protocols are essential to monitor compliance. New concepts and techniques will be required and must be available should a political window of opportunity open in the longer term. As they can take many years to develop, continuing this work remains crucial today.

In this lecture, elements of a possible verification toolbox will be presented. Among them are radiation detection techniques to establish the authenticity of nuclear warheads to be dismantled. Furthermore, nuclear archaeology is introduced as a toolbox to estimate weapons-usable fissile materials inventories based on reconstructing their past production using forensic measurements and computational science.