As I am approaching the study GR, I was wondering if there are softwares that allow a quick visualization of custom metrics, curvature, and particle motion even in the limited context of 2D space.
Playing with equations is fun, but it would be more fun if I could play with various parameters and see the outcome.
Obviously free would be better, but I am open to commercial programs.
I've been looking at this Java archive
General Relativity (GR) Package written by Wolfgang Christian, Mario Belloni, and Anne Cox
It includes a lot of simple programs about Newtonian mechanics, special relativity and general relativity, including the aforementioned GROrbits.
It doesn't permit custom metrics - you are limited to Schwarzschild (regular and rain co-ordinates) and Kerr black holes.
For particle/light motion in 2D space, my nomination would be GROrbits
It's free and requires a JVM to run, there is also a web start version for the brave ;)
Sorry but I've never found anything aimed at visualizing metrics or curvature (apart from plotting programs of course).