"When you sit in a chair like I'm sitting in this chair right now"

"I'm actually hovering over this chair"

"but actually my butt is hovering above the chair by this

just tiny tiny amout" "because of the electrons of my body"

"because the electrons of my butt" "are repelling the electrons of this chair"

"it's not us actually touching the subatomic material of the object"

Is that really true? Does it mean that MC Hammer has just been singing about physics all along?

"Can't touch this !!"

Alas, this doesn't take into account the fact that the universe is quantum mechanical

For example, you probably know that electrons behave like spread-out waves

and from chemistry, you probably also know

that it's perfectly fine for two negatively charged electrons

to share the same energy level of an atom or a molecule

as long as they have their intrinsic spins oriented in opposite directions

So, even though electrons repel each other

their wave packets can overlap.

For example, check out this image of a ring of iron atoms

sitting on a surface of copper.

see the overlap of the spread out electrons? Now, would you call that touching?

If you look at a dictionnary, touch is usually defined

as physical contact. Well, contact is defined as

touching physically. Not much help.

But most of people have this intuitive idea that

touch is something like two solid objects

so close together there is no space between them.

The trouble is this doesn't have anything to do with overlapping

waves which, as we know, are how electrons actually behave.

So, it seems that touch is a word that may just be

incapable of describing the actual universe as we understand it today.

Either that, or we should change our notion of touch

to mean interaction at short distance which is really what happens

between electrons when you sit on a chair.

But, regardless of whether or not we ever actually touch anything

I think that when we talk about the electromagnetic repulsion

of your butt and your chair, what we are really trying to say is

Hey! Remember how cool it is that we are made of atoms and molecules

and that other people made of atoms and molecules

were clever enough to figure that out.

Now, that is touching.

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