A higher-order Skyrme model

摘要: We propose a higher-order Skyrme model with derivative terms of eighth, tenth and twelfth order. Our construction yields simple easy-to-interpret Lagrangians. first show that Skyrmion proposed by Marleau has an instability in the form baby-Skyrmion string, while static energies our are positive definite, implying stability against time-independent perturbations. However, we also find Hamiltonians possess two kinds dynamical instabilities, which may indicate respect to time-dependent Different from well-known Ostrogradsky instability, instabilities intrinsically nonlinear nature due fact even powers inverse metric gives ghost-like kinetic-like term. The vacuum state is, however, stable. Finally, at sufficiently low energies, simplest cases, stable