I have spent the better part of the last 12 years and a large chunk of the last 35+ trying to understand the concepts spoken of here by Bhagwan Maharshi. It describes how our reality is constructed in terms beyond our 3 dimensional constraints and accounts for awareness - thereby resolving the mysteries of quantum entanglement across infinity and Einstein's speed of light paradox.

The "light" of which Ramana speaks is not the visible kind that we normally think of. He is referring to another kind that indicates potential across an infinite plane of awareness. Its' transmission is instantaneous on that plane while on this physical plane it takes cause and effect TIME to reach the end. This is why the speed of light is a constant no matter what the velocity of the observer (thus violating Newton's mechanical laws). The potential is instant and infinite .... but the physical effects take time to catch up. Like watching an explosion on a distant island - by the time you see and hear it the whole event has already happened. The total breadth of the potential was transmitted instantaneously - but the wave of cause and effect takes a bit to reflect that in this physical plane.

This transmission of potential is the Bhagwan's Light. It is an infinite, binary sign that indicates potential difference which is the base rule of existence - "Potential goes to where it ain't".