an empty set = nothing.
Anyway the reality is the physics of it. Physics is anything that exists. What is existence? An atom exists because it effects something. Therefore it is effects that cause existence. If there are no effects then there is no existence.
Example A: There is a ball colliding with another ball. The two balls exist, because they can be measured. Balls bounce on other balls. Photons bounce off the ball into measuring instruments.
Example B: There is a ball, but the ball just tunnels through another ball and does not effect it. Photons tunnel through the ball. The ball doesn’t even interact with any exotic particles in any measurable way. The ball doesn’t even emit gravity. Therefore, the ball does not exist.
The way I look at it is, like this.
big bang > matter forms > planets form > life forms > brain forms > photons enter retina > retina gives signals to brain > brain sends data (perhaps unintentionally?) to consciousness
therefore, consciousness is the final node of existence’s effect chain. If there is no consciousness, there is no existence. Things that “exist”, such as faraway planets, are data, information, knowledge. For example, you write in a book the XYZ coordinates of a planet, or take a picture of the planet.
So when someone says “the tree exists even if noone is around the forest!” they are not wrong. The tree exists like a data, or information. For example. If you step on a train tracks and get ran over by a train, the train causes both you and the train to no longer exist. However, you will soon reincarnate into a new body, then you will exist, and then the data of the train will exist, because the data remains consistent. So the data of the universe remains pretty much consistent and such. So in a data sort of way, it “exists” but is hidden when consciousness is hidden. And also relies on assumptions. For example, when we reincarnate, we assume we will reincarnate into the same universe, but are not totally sure.
Anyway, the point is, it may even be theoretically possible to destroy all of existence. Existence is effects. If you could harmonize or order everything, such that no collisions take place, then there are no effects. Basically, if there is some way to stabilize the chaos, and some how make no more interactions take place. But the tech is very futuristic and Idk if possible.