In the RV, there are seven distinct principles which are referred to by various epithets such as sapta vāņi, seven voices, sapta nadyaĥ, seven rivers, seven rişhis etc. They are the different levels of consciousness. It is worth emphasising that RV has more than forty distinct words occurring in several hundred verses dealing with consciousness. The different grades of consciousness in the ascending order are: matter, life-energy, mind, light and the highest triple of existence-knowledge and bliss. At the level of matter, the “density” of consciousness is least whereas it is highest at the highest triple level. There is a world associated with each principle of consciousness displaying its manifestation. These are: The earth, bhu, bhūmi or pŗthvi, the world governed by material principle, the heaven dyau, the realm of the Divine Mind dealing with all aspects of the mental world. The two together, heaven and earth, are called as rodasi. Between these two worlds is the antariksha or rajas which is the world of all the life-energy, which is the basis of all the plants, animals and the vital aspect of mankind, the realm of emotions, feelings, passions, hopes, fears and love. These three worlds constitute the lower three. The fourth world beyond these three is called svar, the world of Light, the native home of all the devās. It is also referred to as the uru loka or u loka. Beyond this realm is the supreme triple worlds tridhātu in RV, sat-chit-ānanda or existence, consciousness and bliss in Upanishads. Thus the cosmology consists of five worlds or seven worlds depending on whether we treat the supreme triplet as one or three. The RV has so many different concepts connected with the seven (or five) such as seven rişhis, seven potent words, seven rivers or waters etc. It is a mistake to regard these seven rivers as referring exclusively to the seven physical rivers in the north-western Indian sub continent.
There are also subdivisions of these worlds such as the three earths and three heavens etc.
Clearly there is a hierarchy of the worlds in terms of consciousness. The consciousness is at its height in the triple world tridhātu and least in the world of matter. In the highest triplet the Supreme Being, the ONE is in the state of oneness and there is no manifestation. The one becomes the many in the fourth world svar, the beings in this world being the devās. But each deva is conscious of the unity with the ONE. There is no conflict. The multiplicity is intimately tied to the One. In the three lower worlds there is only partial remembrance of their origin from the ONE. It is worth stating that the heaven dyau is not merely a world one goes to after one’s death.