To float.

At first glance, the idea of pedestrians “floating” at the atomic level seems contradictory to our everyday experience. After all, we feel the ground firmly beneath our feet, and gravity is pulling us down relentlessly. But when we look at the situation from the perspective of quantum mechanics and the structure of matter at the atomic level, the idea of “floating” suddenly becomes much more plausible.

1. The structure of matter: Pedestrians and the floor never actually touch

At the atomic level, matter is mostly empty space. Atoms, which make up pedestrians, floors, and all other objects, are themselves made up of a nucleus of protons and neutrons surrounded by a cloud of electrons. This electron cloud takes up most of the space, but these particles are extremely small. As a result, the “solid” matter we experience is actually mostly empty space. In fact, the distance between the nucleus of an atom and its electron clouds is proportionally comparable to the distance between planets in a solar system.

Because matter is mostly empty space, the atoms in our feet and the floor never really come into direct contact. What we perceive as “touch” is actually a result of electromagnetic forces. Electrons in our skin repel electrons in the floor due to the fundamental rule that like particles repel. This creates a very small but measurable distance between the two surfaces, even when we are “standing.” At this scale, pedestrians are literally floating above the floor, separated by the repulsive force of their electrons.

2. Pauli Exclusion Principle: Physics of Non-Touching

The so-called Pauli exclusion principle, one of the basic rules of quantum mechanics, prohibits two fermions (particles such as electrons) from being in exactly the same place with the same quantum state. This means that even when you are standing on the floor, the electrons in the atoms of your feet and the floor cannot be in the same position. This creates a strong “quantum force” that effectively prevents the atoms of your foot and the floor from ever actually merging. Again, you can say that you are not actually touching the floor, but rather floating on a quantum wave of repulsion.

3. Gravitational vs. Electromagnetic Forces

The force of gravity pulling us toward the Earth is extremely weak compared to the electromagnetic forces between atoms. This may sound surprising, given that gravity anchors us firmly to the Earth. But the repulsive force between the electrons in our feet and those in the floor is orders of magnitude stronger than gravity. This is what keeps us from sinking through the floor, despite gravity pulling us down. It is this repulsion that keeps us “floating,” even when we are standing still.

4. Casimir Effect: Quantum Fluctuations and Pressure of Empty Space

At the atomic level, other quantum phenomena also play a role that can create a floating effect. The Casimir effect is a quantum mechanical phenomenon in which two uncharged, closely spaced surfaces experience an attraction due to fluctuations in the quantum field between them. Although this effect is typically observed at very small distances, it illustrates that even empty space between objects can contain quantum fluctuations that contribute to their interaction. This effect further supports the idea that objects (such as a foot and a floor) never quite touch, but always maintain a quantum distance.

5. Conclusion: Floating on a quantum scale

At the macro level, it seems like we are standing firmly on the ground, but at the atomic level, the story is very different. Quantum mechanics shows that no atom in a pedestrian’s feet ever actually comes into contact with the atoms in the floor. The electromagnetic repulsion forces between the electrons, together with principles such as the Pauli exclusion principle, ensure that the pedestrian is effectively floating above the floor, albeit on an extremely small scale. What we experience as “standing” is actually the result of the counteraction of these quantum forces that keep us balanced, without any direct contact.

So, while we may not feel like we are floating, the reality at the atomic level is quite different. Most pedestrians, and indeed everything in the world, float gently above the surfaces they think they are touching.