Planetary Science Seminar

I will discuss two topics relevant to the evolution of planetary systems, eccentricity evolution of giant planets within their natal disks, and a new nonconservative action formalism that can be used for N-body dynamics.

In the first part of the talk I will show how entropy gradients within the disk can modify the non-coorbital corotation torques which dominate the eccentricity evolution for giant planets, and that when insolation heats the gap in the disk due to the giant planet, eccentricity can be pumped. This may have a signature in the existing radial velocity data, which may bear the imprint of the disk structure as a function of metallicity.

In the second part, I will briefly outline a new nonconservative variational principle that we have recently developed, which allows for nonconservative processes to be generically modelled with an action. I will demonstrate how this allows for the formulation of nonconservative variational integrators: numerical integrators with the Noether charge (Energy, angular momentum etc) accuracy properties of symplectic integrators but for systems that have dissipation or other nonconservative physics (e.g. tides, radiation reaction, drag).