What is the function of cycle norm P and cycle norm E?

Cycle norm P and cycle norm E are measures used in the analysis of dynamical systems, particularly in the study of periodic orbits. Cycle norm P typically refers to the norm associated with the phase space of periodic solutions, while cycle norm E is related to the energy associated with those solutions. Together, they help characterize the stability and behavior of cycles within a system, providing insights into their dynamics and potential transitions.