In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

One form of resonance posited to describe these objects occurs where the difference between the pattern and co-rotation frequencies is an integer quotient of the epicyclic frequency. Those resonances exist in the theory of these objects as density waves in a gravitational plasma dispersion relation; those waves are only quasi-stable as these objects cannot be stable due to the so-called winding problem. The aforementioned resonances are named for Lindbladt and the aforementioned theory for (*) Lin and Shu. The rotation rate of these objects increases with luminosity according to the Tully-Fisher relation. Like their elliptical counterparts, they generally contain a red nucleus. Some of these galaxies contain bars. FTP, identify this common type of galaxies, exemplified by the milky way, characterized by their swirling appearance.
Science