This happened a few years back. I was hanging out with my friend, let’s call him Jack. We decided to take two tabs of some somewhat strong acid tabs. The dose was probably somewhere around 150 ugs per tab. About an hour in we really started to feel it. We looked at each other and couldn’t stop laughing, it was an awesome experience. The location we were in was my old house in the Colorado mountains near Estes park. This meant we had plenty of space and privacy to play loud music and yell at the stars like primitives. I was seeing all sorts of unexplainable shapes. I thought to myself, “I can see all the atoms in the air!”. As I thought this, I saw large groups nucleus surrounded by electron orbitals that rapidly spun around the nucleus. Eventually as the trip strengthened, we decided to go the basement where the TV and Sound system was. I layed down on a bean bag chair and looked at the ceiling which was made of these fantastic squares that resembled almost flat pyramids. As I looked at these squares, they started the distort and morph. The squares were now morphed into Rhombuses! Suddenly the sides of the shape disappeared and everything EXPLODED into a white light. I was transported to this realm of Quantum relativity gridlock as the “ground” looked like rolling hills of strange mathematical graphs. The sky was pure white void with no end. It was rapidly changing from white to different colors. I realized where I was and as I did this I was shot back to my body. I felt as if I hadn’t been breathing for a lifetime. I was fascinated. Was this my brain perceiving a 2-dimensional square as a 4-dimensional plane that looked beyond the 2-3 dimensional reality that we experience? This may be one possibility.