Eli5 Why do we feel things physically the way we do?


Correct me if I’m wrong, but since we are technically never really touching anything due to the electrons within our body repelling the electrons that make up an object (eg. A chair) I’m technically hovering above it by an unfathomably small distance. Why is it I can still feel the texture of the chair (or anything actually) if I’m not really touching it?

Thanks a lot (:

In: 1

Your hand might be hovering a microscopic distance from the surface of the chair but the electrons in the chair still push against the skin on your hand. The nerves in your hand feel this pressure and register them as touch.

The atoms in the chair are exerting a (non-contact, based on your definition of touch) force on you as you ‘touch’ it (hence you don’t phase through the chair). Your body interprets the pressure applied to your atoms as touch.

Take two bar magnets and point the negative poles towards eachother.

Now try to push them together – you’ll feel a force between them long before they actually collide.

Atoms are surrounded by a negatively charged shield of electrons, and so they exert this same electromagnetic force on eachother without any actual “contact” between the particles.

This force is tremendously powerful at close range, and makes up the solid world we perceive.

Atoms pass through your skin, so do huge complex molecules and salts. Your skin soaks up absorbs atoms like water, benzenes and chemicals mercury, isocyanates, PCBs,acrylates, and pharmaceutical products such as steroids and nicotine you touch go right through your skin eventually be processed by your liver or kidneys.

Humans can’t even feel any bumps smaller than about 12nanometers in size we just perceive as smooth.

Things we’ve been taught at school are usually simplified so that they allow us to understand why things happen and the relationships between different things. For example, electrons don’t actually circle around the nucleus of atoms like planets circle around the sun.

Instead, it’s more accurate to think of electrons like a horde of insects where you can’t easily spot a single insect because of their speed although you can see the entire horde.

The path electrons take around the nucleus varies. Some move faster and some move slower. However, each individual electron generally stays on the same path. Sometimes the paths can change but two electrons can never move on a similar path. According to something called Pauli exclusion principle, two electrons can never have the same quantum state or, put more simply, move along a similar path.

Although electrons move indefinitely, they need energy to change their path to a more energetic one. Correspondingly, the electrons will give off energy when they change to a lower energy path.

For example, an electron may move to a higher energy path when it’s hit by light. For example, light hitting something like a desk won’t get very far because all the electrons “like” to absorb some of its energy. This energy is released instantly and we see this as reflections and colors. This is why the desk looks solid.

Now, when you touch the same desk, the electrons in your hand move close to the electrons of the desk. When this happens, electrons change paths. This is because electrons can’t move along a similar path. So electrons of atoms moving close to each other have to change their paths to higher energy paths. This time, though, the energy doesn’t come from light but the force moving the atoms closer to each other. In the case of a hand moving towards a desk, there are billions and billions of electrons moving closer to each other and all of them need to change their paths which requires a lot of energy. So much, in fact, that the hand is stopped and can no longer be moved closer to the table. This is the main reason why things feel solid.

An another reason our hand is stopped instead of moving through solid objects is that every electron has a negative electric charge. Similar charges repel each other which makes it even more difficult to move objects very close to each other.