I've always wanted to get a tattoo, but I knew that whatever design I chose, I wanted it to be something I designed.
The design originated from a design I fleetingly came across and have since lost of a symbol describing a measure of existential maturity when one is willing to admit to not knowing something, and, further, is accepting of that ignorance. The willingness to admit one has room to grow. This questioning nature is described in the designs overall "question mark" shape.
As I feel that message connects with the themes of quantum mechanics, where there is an innate gap in what one can know about a particle's state, I wanted to include some symbol of that in the design. Thus I added the wave to accompany the dot in the "question mark," symbolizing matter's wave-particle duality.
I also study planetary sciences and felt that should be included, which is where the smaller circle and the line through come in. They are meant to represent an orrery, or a model of a planet-and-moon dynamical system.
The design to the left was the first draft, which I liked but felt it needed work. It felt like there was too much downwards "motion" to the graphic, so I flipped the moon across the slash. That choice helped balance the design. Another aspect I chose to remove was the notation symbol separating the particle and wave. It felt unnecessary, and so I removed it. One final adjustment I made to connect the wave to the three-quarter "planet," was slicing off a bit of the circle so there's an invisible cut-off point shared between the circle and wave.
Finally, I arrived at the final design.