Overview

KerrGeoPy is a python library for computing bound timelike geodesics in Kerr spacetime. It is intended for use in computing orbital trajectories for extreme-mass-ratio inspirals (EMRIs). It implements the analytical solutions for plunging orbits from Dyson and van de Meent, as well as solutions for stable orbits from Fujita and Hikida. The library also provides a set of methods for computing constants of motion and orbital frequencies, and can generate plots and animations like those shown below.

Installation

Install using Anaconda

conda install -c conda-forge kerrgeopy

or using pip

pip install kerrgeopy

Note

KerrGeoPy uses functions introduced in scipy 1.8, so it may also be necessary to update scipy by running pip install scipy -U, although in most cases this should be done automatically by pip. Certain plotting and animation functions also make use of features introduced in matplotlib 3.7 and rely on ffmpeg, which can be easily installed using homebrew or anaconda.

See Getting Started for basic usage. See the API Reference below or the Modules page for a complete list of classes and methods.

Tutorials

• Getting Started
  • Stable Bound Orbits
  • Orbital Properties
  • Plunging Orbits
  • Alternative Parametrizations
• Orbital Properties
  • Constants of Motion
  • Frequencies of Motion
  • Stability
  • Spacetime
• Trajectory
  • Stable Bound Orbits
  • Plunging Orbits
  • Four Velocity
• Graphics
  • Plots
  • Animations

API Reference

StableOrbit(a, p, e, x[, initial_phases, M, mu])	Class representing a stable bound orbit in Kerr spacetime.
PlungingOrbit(a, E, L, Q[, initial_phases, ...])	Class representing a plunging orbit in Kerr spacetime.
Orbit(a, initial_position, initial_velocity)	Class representing an orbit in Kerr spacetime defined using initial conditions.
KerrSpacetime(a[, M])	Class representing spacetime around a black hole with mass \(M\) and spin parameter \(a\)
constants	Module containing functions for computing the constants of motion for an orbit in Kerr Spacetime.
frequencies	Module containing functions for computing frequencies of motion for orbits in Kerr spacetime.
initial_conditions	Module containing functions to compute orbital properties from initial conditions
units	Module containing functions to convert between geometrized units and physical units.

Indices and tables

• Index

• Module Index

• Search Page