It feels like a leftover from creation. Like the cosmic microwave background perhaps - or dust (if you believe Phillip Pullman)
"In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return" (Genesis 3:19)...
Unlike ordinary particles, Dust is conscious. It falls from the sky, is attracted to people, and wears off onto objects made by people. This makes it of great interest to the Church, which believes that it may be the physical manifestation of Original Sin.
https://en.wikipedia.org/wiki/Dust_(His_Dark_Materials)
That's how I visualize it anyway...
