Accounting for systematic theory errors in nuclear calculations

Abstract:  As theoretical calculations of nuclear structure and reactions become more accurate and precise, there is increasing awareness of the need for better uncertainty quantification (UQ). Theory errors are usually systematic rather than statistical. Examples are the errors from using a finite harmonic oscillator basis and the errors from omitted higher-order terms in an effective field theory (EFT) expansion. I will focus on UQ in nuclear EFT calculations and illustrate how a Bayesian framework can be used to avoid overfitting of EFT constants, propagate EFT truncation errors, and diagnose whether the EFT is working as advertised.