What do Multiple Planet Systems Teach Us About Planet Formation?
Radial velocity searches have discovered over a dozen nearby stars which harbor multiple planets. In several of these planetary systems, the planets’ gravitational interactions cause significant deviations from Keplerian orbits on secular and/or orbital timescales. Studying the dynamical evolution of these systems can provide insights into the history and formation of these systems. I will summarize recent observational developments and the current understanding of these systems. Then I will focus on two of the best constrained planetary systems, GJ 876 and Upsilon Andromedae, and demonstrate that they have very different formation histories.
