Before revision: Recently it has been revealed that the equilibrium hydrogen-bond breathing dynamics of terminal base pairs in short DNA exhibit a power-law relaxation similar to that in the time-resolved Stokes shift experiments with an intercalated coumarin probe. Herea simple theory is proposed that relates the Stokes shift signal to the statistics of Poincar\'e recurrences in the base-pair breathing.
After revision: Recently it has been revealed that the equilibrium hydrogen-bond breathing dynamics of terminal base pairs in short DNA exhibit a power-law relaxation attributable to weak Hamiltonian chaos, with parameters similar to experimental data. Here, the relationship is studied between this motion and spectroscopic signals measured in DNA with a small molecular photoprobe inserted into the base-pair breathing.