  A key challenge in complex design problems that permeate science and
engineering is the need to balance design objectives for specific design
elements or subsystems with global system objectives. Global objectives give
rise to competing design pressures, whose effects can be difficult to trace in
subsystem design. Here, using examples from arrangement problems, we show that
the systems-level application of statistical physics principles, which we term
"systems physics", provides a detailed characterization of subsystem design in
terms of the concepts of stress and strain from materials physics. We analyze
instances of routing problems in naval architectures, and show that systems
physics provides a direct means of classifying architecture types, and
quantifying trade-offs between subsystem- and overall performance. Our approach
generalizes straightforwardly to design problems in a wide range of other
disciplines that require concrete understanding of how the pressure to meet
overall design objectives drives the outcomes for component subsystems.
