Research Log – Introduction
Since this is the first entry in my new research log, I’ll provide an overview of what I will be working on for the foreseeable future.
My goal is to enter the field of galactic dynamics and eventually write my own simulation code or modify existing codes in order to improve our understanding of the processes at work in the formation and evolution of galaxies. Galaxies are rather complex systems and properly modeling their behavior requires the inclusion of stellar evolution, gas dynamics, plasma physics (MHD), gravitation, and cosmology. One has to model interactions between galaxies and properly model the feedback between AGN and host galaxies. Consistently modeling AGN feedback in galactic evolution of course requires an understanding of the process by which AGN are triggered. My plan for the summer is to:
- Read Galactic Dynamics by Binney and Tremaine in order to get a historical perspective on the theoretical work which had been done up until the late 1980s when the book was published.
- Read Annual Reviews relating to galaxies and AGN.
- Read papers by, Gabriela Canalizo and Bruno Jungwiert.
- Read simulation papers by Philip Hopkins, Debora Sijacki, and any others that seem useful.
- Learn the basics of smoothed-particle hydrodynamics.
- Write a few simple codes to get back in practice.
I began working on July 1st. I’ve read the first three chapters of Galactic Dynamics and today I started the fourth chapter. I’ve worked some of the problems along the way. Thus far the book is mostly a review of classical mechanics with a few extra applications. The situations described thus far are highly idealized; they are based entirely on smoothed potentials assuming Newtonian gravitation is perfectly valid. I’ve started the process of collecting papers to read. I’ve read one paper by Canalizo and Jungwiert. I already read a few papers by Hopkins et al. and Sijacki et al. about a month ago, but there are plenty others to read.
The three programs that I want to write this summer to get in practice are:
- A simple orbit tracer. Given a potential, an initial position, and initial velocity, calculate the orbit.
- A simple Newtonian N-body simulation with particles of different masses. I won’t bother making it efficient, so it will only be able to handle a few particles.
- A modification to program #2 which assumes that gravitational signals travel with finite speed. The results can be compared with those of program #2.