As for "nothingness," please sit comfortably, close your eyes, breathe naturally, and put your attention on your breath. Be it immediate, days, months, years, decades, or lifetimes, what you perceive will be space (akasha) and a growing sense of expansion. This is one of Lord Buddha's techniques for liberation. "Nothingness" is quite real. As for "zero," relax and try to imagine the universe, but with you no longer a part of it. You may find this an impossible task. It is not. The universe, without your ego, is zero, and gives you a glimpse of the ultimate reality of eternal abstract-bliss consciousness. The perfected being Lao Tzu gave a path to find your true nature.