Summary

After having studied this lecture, you should be able to

• describe the density-morphology relation for galaxies
• explain what is the Tully-Fisher relation, and derive what it implies for the mass-to-light ratio and surface brightness of spirals
• explain the Faber-Jackson and Fundamental Plane relations for Ellipticals, and derive what the fundamental plane relation implies for the mass-to-light ratio of ellipticals
• explain how Tully-Fisher and Fundamental Plane relations are used as standard candles.
• explain what is the luminosity function of galaxies and sketch it.