Disarming North Korea with physics: How can verification help resolve the nuclear crisis?

How to stop Kim Jong Un's nuclear path? Despite de-escalation hardly being in sight, concepts must be ready. Should the complete denuclearization be required for political and economic guarantees, or at first only a freeze of the nuclear programme? Either approach raises scientific challenges: How could inspectors verify North Korean compliance? Two key issues are quantifying how much fissile material was produced in the past to assess how many weapons could be built and must be dismantled, and determining the present non-production (under a freeze). This talk introduces the North Korean fissile material production programme and inspections carried out in the past, as well as concepts for novel methods to quantify past production. This includes measurements in shut-down reactors to determine the neutron fluence and to distinguish past plutonium from tritium production, measurements of the isotopics and mass of radioactive waste, and analyzing operational records coupled with fuel cycle simulations. Beyond North Korea, such methods will be needed to verify global nuclear disarmament.