#2160: QuasiLocalMeasures qlm_spin doesn't work for spins not aligned along the z axis
| Reporter: | |
| Status: | wontfix |
| Milestone: | |
| Version: | development version |
| Type: | bug |
| Priority: | minor |
| Component: | EinsteinToolkit thorn |
Changes (by Roland Haas):
| status: | wontfix (was new) |
Einstein Toolkit version: ET_2018_02.
Parameter file: qc0-mclachlan.par in einsteinexamples with the additional parameter TwoPunctures::par_S_plus [0] = +0.3
Problem: The diagnostic qlm_spin[0] returns a spin of 0, whereas the expected one should be 0.3.
If instead of TwoPunctures::par_S_plus [1] = +0.3 one sets
TwoPunctures::par_S_plus [2] = +0.3, qlm_spin[0] is correctly
outputting 0.3
This happens because QuasiLocalMeasures finds in both cases the rotational Killing vector d/dphi (as seen setting QuasiLocalMeasures::veryverbose = yes), which is correct in the second case (when the axis aligned with the z-direction), but doesn't sound right when the rotation is with respect to the x-axis.
Changing QuasiLocalMeasures::killing_vector_method to axial or gradient does not change the outcome.
Best regards, Gabriele
Keyword: QuasiLocalMeasures
Comment (by Roland Haas):
Works as designed. This limit should be documented.
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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2160/quasilocalmeasures-qlm_spin-doesnt-work