Hitherto, we wrongly believed that we experience the real world in the Real Dimension, hence, the realm of the Mind Dimension remained oblivious, even though we have always only experienced the worlds that are manifested in only the Mind Dimension.
If only you have comprehended what the Mind Dimension is, then you can also comprehend what the Real Dimension is; otherwise reality of both realms will remain totally obscured from your awareness. In fact, we can't discuss anything substantial about the Real Dimension without reference to the Mind Dimension, as all our abstractions of the nature of the real world in the Real Dimension is but simply abstractions construed by our brain-mind system and manifested in a given manner in the Mind Dimension.
Through scientific research we commonly make reasonable guesses about the nature of the real world in the Real Dimension with which to build technologies, but scientists do not yet know the true nature of the real world. We only know what the human brain-mind system construes it to be by its design governed by the constructing code provided in the DNA. As the human brain-mind system evolves, our knowledge and perceptions of the world evolves. Some day into the distant future, when we have evolved into a new species with highly evolved brain-mind systems, the perception of the world won't be the same as today.