when we talk of unmanifest, we talk of transcendental, real transcendental, lying beyond the range of the three Gunas, even beyond the unmanifest state of the three Guqtas. So three Guryas we find on two levels: one active, which means the whole relative life; one is non-active, the basis of all activity. And Brahm is transcending even that, and that unmanifest is Absolute. That is called Purusha also. Many times in Upanishads and Brahma Sütra that is also called Parama-Ätman.
Atman is with the individual. What is the difference in Atman and Brahm? Atman is with reference to the individual; Brahm is the same material, but with reference to the universe. The Self of the entire universe is Brahm. The Self of the body is Ätman. Material is the same.
At the junction point between the manifest and the unmanifest, all the Laws of Nature functioning within the unmanifest sprout into manifestation. It will be possible for a scientist whose awareness is established at this level to directly know, through an inward process, any Law of Nature. This will mean a complete revolution in science.