  The preponderance of matter over antimatter in the early universe, the
dynamics of the supernovae that produced the heavy elements necessary for life,
and whether protons eventually decay -- these mysteries at the forefront of
particle physics and astrophysics are key to understanding the early evolution
of our universe, its current state, and its eventual fate. DUNE is an
international world-class experiment dedicated to addressing these questions as
it searches for leptonic charge-parity symmetry violation, stands ready to
capture supernova neutrino bursts, and seeks to observe nucleon decay as a
signature of a grand unified theory underlying the standard model.
  The DUNE far detector technical design report (TDR) describes the DUNE
physics program and the technical designs of the single- and dual-phase DUNE
liquid argon TPC far detector modules. Volume II of this TDR, DUNE Physics,
describes the array of identified scientific opportunities and key goals.
Crucially, we also report our best current understanding of the capability of
DUNE to realize these goals, along with the detailed arguments and
investigations on which this understanding is based.
  This TDR volume documents the scientific basis underlying the conception and
design of the LBNF/DUNE experimental configurations. As a result, the
description of DUNE's experimental capabilities constitutes the bulk of the
document. Key linkages between requirements for successful execution of the
physics program and primary specifications of the experimental configurations
are drawn and summarized.
  This document also serves a wider purpose as a statement on the scientific
potential of DUNE as a central component within a global program of frontier
theoretical and experimental particle physics research. Thus, the presentation
also aims to serve as a resource for the particle physics community at large.
