The Galactic Core is considered to be at the center of the 15 dimensional Universal Time Matrix, in which connects to the level of Geomantic Entity that we were before we entered manifestation and became individuated. The Galactic Core is connected to 8D.
Universal Time Matrix
The Universal Time Cosmology of Twelve Dimensions of Simultaneous Time-Space Cycles within a Fifteen Dimensional Wave Spectrum. Each Harmonic Universe is equal to the Triad of Spiritual Identity that our consciousness evolves through as our Personality (1D-2D-3D), Soul (4D-5D-6D), Oversoul (Monad) (7D-8D-9D), Avatar Christos (10D-11D-12D) and Founder Consciousness (13D-14D-15D).