Disturbances of Rotational Motions for String Models of Hadrons and the Stability Problem

Slight disturbances of a classical rotational motion (uniform rotation of a system) are considered for a relativistic string with massive ends and for the q-q-q and Y baryon string models. It is shown that for a string with massive ends this motion is stable in the linear approximation and the slight perturbations are representable by a series each term of which describes a standing wave of certain frequency. These modes make it possible to simulate various excited states of hadrons. At the same time, for the q-q-q and Y baryon string models the instability of rotational motions has been proved: exponentially growing modes have been detected in their perturbation spectra.