One might make a parallel between the field strength $F=dA$ and the torsion two-form $dd{t}^{\prime }$ (cf. Refs. [67, 68, 69]) associated with these two strings, which are distributional.

This is consistent with the fact that the GSF spinor equation [74, 75] is chiral (cf. Ref. [56]).

Note that $(f(\tilde{Z}){)}^{-h-1}$ could be interpreted as the half-Fourier transformed scattering amplitude of a massive object absorbing a negative-helicity force carrier [79].

This function can be written as $i{\tilde{Z}}^{\mathrm{A}}{u}_{\mu }({\gamma }^{\mu }{{)}_{\mathrm{A}}}^{\mathrm{C}}{\overline{I}}_{\mathrm{C}\mathrm{B}}{\tilde{Z}}^{\mathrm{B}}$ by employing the infinity twistor ${\overline{I}}_{\mathrm{A}\mathrm{B}}$.

It might be that the color-to-diffeomorphism replacement rule [94] directly applies at the level of the chiral current so that $A_{1\dot{\alpha }}\sim {\tilde{o}}_{\dot{\alpha }}$ maps to $h_{1\dot{\alpha }1\dot{\beta }}\sim {\tilde{o}}_{\dot{\alpha }}{\tilde{o}}_{\dot{\beta }}$.

Finding a diffeomorphism bridging between the two would shed an insight. We thank Andres Luna for suggesting this direction.

The KS metric nicely falls into the BMS category of asymptotically flat metrics [108, 109, 110], with mass aspect $m$, angular momentum aspects zero, and $C_{\zeta \zeta }=4M{\tilde{\zeta }}^2/(1+\tilde{\zeta }\zeta {)}^2$, $C_{\tilde{\zeta }\tilde{\zeta }}=0$.