  I consider some promising future directions for quantum information theory
that could influence the development of 21st century physics. Advances in the
theory of the distinguishability of superoperators may lead to new strategies
for improving the precision of quantum-limited measurements. A better grasp of
the properties of multi-partite quantum entanglement may lead to deeper
understanding of strongly-coupled dynamics in quantum many-body systems,
quantum field theory, and quantum gravity.
