TeukEvolution.jl

Buyer Beware: this code is a work in progress

TeukEvolution.jl contains routines to evolve the Teukolsky equation in a horizon penetrating, hyperboloidally compactified system of coordinates. One day, this code may replace the second order Teukolsky code teuk-fortran-2020. At the moment, this code can only do linear evolution of fields right now. If you want to compute the second-order perturbation of a black hole, you will have to use the teuk-fortran-2020 code.

Initial data

There are two choices of initial data.

1. Gaussian pulse initial data.

2. Quasinormal mode initial data. These need to be read in from HDF5 files that are generated with TeukolskyQNMFunctions.jl.

See the examples directory for two example paramter files.

Visualization

The output is currently saved as .csv files, which stored in columns at a fixed time (R,Y,value). We use the 2d plotter in the sci-vis to visualize code output.

For example, once you've cloned the sci-vis repository, you can open the 2D plotter via

python3 ~/sci-vis/plotters/plotter_2d.py

This should open a gui, from which you can open a field file, e.g. lin_f_re_2.csv, which is the m=2 component of the real part of the linear field (e.g. $\Psi_4$).

Contact

ripley[at]illinois[dot]edu

Citation

If you use this code, the best thing to cite right now would be the below reference, as it describes the newest version of the code.

@article{Zhu:2023mzv,
    author = "Zhu, Hengrui and Ripley, Justin L. and C\'ardenas-Avenda\~no, Alejandro and Pretorius, Frans",
    title = "{Challenges in Quasinormal Mode Extraction: Perspectives from Numerical solutions to the Teukolsky Equation}",
    eprint = "2309.13204",
    archivePrefix = "arXiv",
    primaryClass = "gr-qc",
    month = "9",
    year = "2023"
}

If you make use of quasinormal mode intial data, please also cite

@article{Ripley:2022ypi,
    author = "Ripley, Justin L.",
    title = "{Computing the quasinormal modes and eigenfunctions for the Teukolsky equation using horizon penetrating, hyperboloidally compactified coordinates}",
    eprint = "2202.03837",
    archivePrefix = "arXiv",
    primaryClass = "gr-qc",
    doi = "10.1088/1361-6382/ac776d",
    journal = "Class. Quant. Grav.",
    volume = "39",
    number = "14",
    pages = "145009",
    year = "2022"
}

The main ideas behind this code (e.g. using a spectral basis to compute the GHP angular derivatives) were originally explained in the below article. Granted, this reference is more focused on quadratic mode coupling, so only cite it if you feel its relevant to your use case.

@article{Ripley:2020xby,
    author = "Ripley, Justin L. and Loutrel, Nicholas and Giorgi, Elena and Pretorius, Frans",
    title = "{Numerical computation of second order vacuum perturbations of Kerr black holes}",
    eprint = "2010.00162",
    archivePrefix = "arXiv",
    primaryClass = "gr-qc",
    doi = "10.1103/PhysRevD.103.104018",
    journal = "Phys. Rev. D",
    volume = "103",
    pages = "104018",
    year = "2021"
}