Orbits in strongly curved spacetime

[Naty1]

Came across some interesting animations here...test particle orbiting a black hole:

Orbits in strongly curved spacetime
http://www.fourmilab.ch/gravitation/orbits/

In strong gravitational fields, General Relativity predicts orbits drastically different from the ellipses of Kepler's laws. This page allows you to explore them.

The precession advance of Mercury [which helped confirm Einstein's theory] is described under ...

The Gravitational Effective-Potential

...In Einstein's theory, the inability of the particle to orbit at or above the speed of light creates a “pit in the potential” near the black hole. As the test mass approaches this summit, falling in from larger radii with greater and greater velocity, it will linger near the energy peak for an increasingly long time, while its continued angular motion will result in more and more precession. If the particle passes the energy peak and continues to lesser radii, toward the left, its fate is sealed—it will fall into the black hole and be captured...

Enjoy.

 

[m4r35n357]

I learned a lot from looking at the source code for that program, but was not happy with the "gravity well" animation because AIUI that should be a spacelike surface . . .
Here is a similar but more advanced program, again with source available:
http://stuleja.org/grorbits/
GROrbits can also simulate light trajectories and those for black holes spinning in the equatorial plane.
I use it as a check for my 4D geodesic simulations.

 

[Sam Gralla]

That ain't nothing. Check out Steve Drasco's stuff,

http://www.tapir.caltech.edu/~sdrasco/animations/index.html

 

[m4r35n357]

That ain't nothing. Check out Steve Drasco's stuff,

Hmm, quite pretty, but a little too read-only for my tastes, not sure how I can learn very much from that.