Adiabatic spherically symmetric initial fluctuation - cmyoo/cosmos GitHub Wiki

Here we will only describe how to perform test calculations and how to check them.
We will not go into the details of the setup here, so please refer to the following PDF file in the source directory.: adiabatic_spherical.pdf.
The main differences from the original source files in this sample code are described in diff_adiabatic_spherical.pdf

Additional initial data file

  • "ini_all.dat": the data file describing the system soon after the horizon formation.
    In the default setting, the time evolution starts from the data given by the data file "ini_all.dat".

How to compile and run

  1. Check if your computer meets the required system environments.
  2. Download the source code and move to the "cosmos/source/adiabatic_spherical" directory.
  3. (If needed) Appropriately rewrite the "makefile".
  4. Compile it by "make".
  5. (If needed) Set the number of threads you use by "export OMP_NUM_THREADS=#".
  6. Run it by "./cosmos".

How to check the result

  • Check the files expected to be generated.

  • Check the contents of the file "out_diff.dat".
    The values show the differences from the expected values listed in "exp_xkl.dat".
    The values are expected to be less than $\sim 10^{-10}$.
    (Most of the values are expected to be at a level of machine precision.
    But values of constraint violations, such as "ham", "hamn", "nM_z", and "M_z", may be slightly larger due to cancellation errors).

  • Plot the apparent horizon profile by using "out_AHfig.dat".
    The gnuplot command to get Fig. 3 in adiabatic_spherical.pdf is the following.
    set hidden3d nooffset
    splot "out_AHfig.dat" usi (($1)):(($2)):(($3)) ind 0 ti "" w l

  • Plot the lapse function on the $x$-axis by using the 1st and 2nd columns in "out_xkl.dat".
    The gnuplot command to get the left panel in Fig. 4 in adiabatic_spherical.pdf is the following.
    plot \
    "out_xkl.dat" ind 0 usi 1:2 ti "lowest layer" with lp,\
    "out_xkl.dat" ind 1 usi 1:2 ti "1st FMR layer" with lp,\
    "out_xkl.dat" ind 2 usi 1:2 ti "2nd FMR layer" with lp

  • Plot the lapse function on the $xy$-plane by using the 1st, 2nd and 3rd columns in "out_xyl.dat".
    The gnuplot command to get the right panel in Fig. 4 in adiabatic_spherical.pdf is the following.
    splot \
    "out_xyl.dat" usi 1:2:3 ind 0 ti "lowest layer" w l,\
    "out_xyl.dat" usi 1:2:3 ind 1 ti "1st FMR layer" w l,\
    "out_xyl.dat" usi 1:2:3 ind 2 ti "2nd FMR layer" w l