  Chain-mapping techniques combined with the time-dependent density matrix
renormalization group are powerful tools for simulating the dynamics of open
quantum systems interacting with structured bosonic environments. Most
interestingly, they leave the degrees of freedom of the environment open to
inspection. In this work, we fully exploit the access to environmental
observables to illustrate how the evolution of the open quantum system can be
related to the detailed evolution of the environment it interacts with. In
particular, we give a precise description of the fundamental physics that
enables the finite temperature chain-mapping formalism to express dynamical
equilibrium states. Furthermore, we analyze a two-level system strongly
interacting with a super-Ohmic environment, where we discover a change in the
spin-boson ground state that can be traced to the formation of polaronic
states.
