摘要: This chapter reviews theoretical work on the stellar dynamics of galaxy disks. All known collective global instabilities are identified, and their mechanisms described in terms local wave mechanics. A detailed discussion warps other bending waves is also given. The structure bars galaxies, effect evolution, now reasonably well understood, but there still no convincing explanation for origin frequency. Spiral patterns have long presented a special challenge, ideas recent developments reviewed. Other topics include scattering disk stars survival thin