There is one Reality. There is no unreality. In dealing with the world separated from Pure Consciousness we are dealing with a non-entity. Such a world does not exist, for it is unreal. Experience shows that Pure Consciousness ever attends every unfolding of a state* [the three states: waking, dreaming, sleeping], endowing it with reality lasting as long as the state lasts, and withdraws it into itself when the state changes. When the next state is called into being, while the previous state abides in memory, the present again under the auspices of Pure Consciousness receives the stamp of reality. Thus, far from Pure Consciousness becoming reduced to non-entity in the abscense of a world perceived, it is, on the contrary, the world that is reduced to a nulity when divorced from Pure Consciousness.
* The three states are identical in essence; in other words, this is its metaphysical substratum. Dream and waking represent the dynamic modes of Pure Consciousness… While unquestionably we pass through three states, we cannot conceive the trinity by means of our intellect, and our knowledge of life cannot be full without a comprehension of the triad. Vedanta sys this trinity is one in fact.
K.A. Krishnaswamy Iyer