Plunging Geodesics Kerr pull request #44
Conversation
Version1 of plunge package working for ISSO, Complex and Real Roots - ISSO currently in separate package to Generic solution file, neither implemented in the original GeoOrbit package yet.
TestPlungesProducingPaperPlots
Package working ISSO for radial param and inclined param. Commit also contain test file with flow and orbital plots, need to include initial conditions and return mino time crossing horizon still
Small bug fixed, now works for ICs. Noticed generic coord tIme solution still is not fully analytic Arctan term is causing issues needs to be massaged to an analytic form.
…canonical keyword Automatic for empty input (instead of "Nan")
Real Root Code has some issues, added all crossing times and fixed format of complex roots file, also added all initial conditions properly.
All fixes seem to be working, just need to run a script to test all possible cases i.e. code works when it should and gives correct error messages when it shouldn't
This reverts commit 8d1284f.
L now works for all allowed r_I and ISSO works for equatorial case now.
MIno time and other outputs improved to correct form
Tests provide in proper Mathematica Test File now
Moved test file to test folder and removed unnecessary additional files
This reverts commit 1ad602d.
This reverts commit 6f8e3e1.
Kernel/KerrGeoPlunge.m
Outdated
| "KerrGeodesics`FourVelocity`"}]; | ||
|
|
||
|
|
||
| KerrGeoPlunge::usage = "Takes either KerrGeoPlunge[a, Generic, En ,\[ScriptCapitalL],\[ScriptCapitalQ]] or KerrGeoPlunge[a, ISSO , RI] for generic Plunges or ISSO plunges respectively and returns a KerrGeoPlungeFunction[..] which stores the orbital trajectory and parameters. Here the ISSO plunges are paramaterised in terms of the choice of the radius of the ISSO for a given a there are range of allowed RI's which correspond to differeing inclinations in the prograde and retrograde directions, if an RI outside this range is given the used is provided with the range of allowed values to re-run the funciton."; |
There was a problem hiding this comment.
We need to think carefully about this interface. Do we want separate functions for ISSO plunges? Or can everything be inferred automatically and unambiguously from context?
There was a problem hiding this comment.
I've reworded this section slightly; the usage is as follows.
For generic plunges you provide either KerrGeoPlunges[a, {e,L,Q}] or KerrGeoPlunges[a, {e,L,Q}, {t0,to,theta0,phi0}] if you want to include initial conditions
For ISSO, one provides either KerrGeoPlunges[a, "ISSORadialParam", RI] or KerrGeoPlunges[a, "ISSOIncParam", theta_Inc] with IC's working the same as the generic case as a final option.
The package defaults to Generic unless the user explicitly inputs an ISSO option which I think should be sufficiently unambiguous but I'm happy to consider alternatives.
There was a problem hiding this comment.
I agree the main issue will be deciding on the interface. This should probably go along with the discussion related to issue #37 and associated pull request #38. We were thinking of having default input parameters as (a,p,e,x) but then allowing associations to be passed if the user wishes to use alternative parameterizations.
We also need to decide if we want KerrGeoPlunges or to wrap this within KerrGeoOrbit
There was a problem hiding this comment.
I'm not sure if parameterization by (a,p,e,x) is overly suitable for plunges. @MvdMeent also mentions in #37 how this parameterization breaks down for plunges. If we wanted a parameterization that works well for all classes of bound geodesics (including plunges), perhaps parameterizing by initial position and velocity, as Vojtech mentions in #37 might be best? Theres probably other reasons for why this might not be a good choice that I'm unaware of though.
If we do decide to wrap KerrGeoPlunges within KerrGeoOrbit, we do have to note the fact that for a large part of the parameter space, a given (a,E,L,Q) gives two solutions, one bound in the regular sense, and another "deeply bound"(plunging). So if we do this, we need to think about if we want the user to have to specify if they're looking for a plunging or bound geodesic when they run the code. Perhaps this isn't an issue if we can parameterize the plunges by (a,p,e,x) or initial positions and velocities, though?
I do think the ISSO case parameterization should be kept largely the same as it currently is however, because the nice thing about those solutions is being able to fully parameterize everything by a single choice of R_{ISSO}.
|
I noticed that the a=0 case does not seem to work. e.g.,
|
|
The package currently doesn't work for the a=1 or a=0 case; I've added an error message that kills the run if either of these choices is made I'll see if the functions can be easily adapted to work in the a=0 case I'm pretty certain there is no easy way to make it work in the extremal case but ill check also. |
Working for a=0 still gives error message for a=1. a=0 case has been extended through the manifold singularity but is still continuous and satisfies the EOM so seems to be working correctly.
closed section opened
|
Both the generic case and ISSO now work for a=0. |
|
Just so we don't forget. Following a meeting on the 24th of Feb. we decided on the following API: KerrGeoOrbit[a,"\[ScriptCapitalE]\[ScriptCapitalL]\[ScriptCapitalQ]"->{0.9,3,1.2},"InitialPhases"->{1,2,4}]
KerrGeoOrbit[a,"\[ScriptCapitalE]\[ScriptCapitalL]\[ScriptCapitalQ]"->{0.9,3,1.2},"OrbitType"->"Plunge"]
KerrGeoOrbit[a,"Subscript[r, ISSO]"->5,"OrbitType"->"Plunge"]
KerrGeoOrbit[a,"InitialPosition"->{1,2,3,4},"FourVelocity"->{1,5,6,7}]This is the main change needed for before merging this pull request and #38 |
Pull request for plunging geodesics in Kerr, Analytic implementation in terms of Mino time, solves for generic plunges given {a,e,L,Q} and can specialise to plunges from the ISSO for parameterizations {a,r_{ISSO}} or {a,\theta_{inc}}. Units test have also been included, and packaged sits on top of existing ones. The only change to existing packages should be the addition of the line "KerrGeodesics
KerrGeoPlunge" in the KerrGeodesics.m run file.