The obvious question is whether the spherically symmetric minimal surface of this kind with stationary induced metric have the physical properties assigned to Schwarschild and Reissner-Nordstöm metrics. The modification of simple calculations done already at 90's for vacuum extremal imbeddings of these metrics leads to an ansatz which gives rise to Newtonian gravitational potential at far away regions. It has also the analog of Schwartschild horizon at which the roles of time and radial coordinate are changed and also another horizon at which the radial direction transforms back to Euclidian so that this horizons is light-like 3-surface at which metric signature changes to Euclidian. Interestingly, there is a recent report about indications that LIGO blackhole has a layer like structure at horizon.
See the new chapter Can one apply Occam's razor as a general purpose debunking argument to TGD? of "Towards M-matrix" or article with the same title.
For a summary of earlier postings see Latest progress in TGD.