One of the fun things to do in meditation is to begin to explore the nature of consciousness and the nature of reality. I've recently contributed some thoughts to the concept of time (particularly some insights about it not being real). Hmmmm. It's really tough to wrap our limited-capacity human brains around the concept that time is merely an illusion. But an even more mystical exploration is the concept that matter is not real. Think about the smallest piece of "you" - whatever that is. Let's say...you're pinky fingernail. Now go in to a single molecule of your pinky fingernail. Now go into the different electrons, protons, and neutrons of that molecule of your pinky fingernail. Now go into the quarks and neutrino's of the neutron of the molecule of your pinky fingernail. There's no thing there. No mass. Just energy spinning in different directions. There is no "you", per se, as a "thing". YOU are only energy, little tiny bits of energy spinning and vibrating and coming in and out of existence. Whoa!!
Here's more from the brilliant physicist - Max Planck
"And so, having studied the atom, I am telling you that there is no matter as such. All matter arises and persists only due to a force that causes the atomic particles to vibrate, holding them together in the tiniest of solar systems, the atom.
Yet in the whole of the universe there is no force that is either intelligent or eternal, and we must therefore assume that behind this force there is a conscious, intelligent mind or spirit.
This is the very origin of all matter.”
Have fun with this. Explore. The wonder and awe of our experience in this dimension!!!