# Electrons can be anywhere unless observed , how does electricity work then?

I watched this documentary, about Quantum physics the other day. Naturally it got me even more confused than I started. But this idea started bugging me yesterday and I googled and found even more confusing answers that made more questions rise.

Well they say that electrons are everywhere, but when observed they are forced to pick an absolute position. At the same time they say that electricity is atoms exchanging electrons (I probably got this one wrong).

This leads me into the funny conclusion that there are theese dwarves constantly staring at individual atoms so our computers can work.

I am really confused now. Someone please bring some light to this topic for me.

• What do you mean by electrons are everywhere? – user36790 Sep 15 '16 at 8:24
• Electrons aren't everywhere. They don't have a specific positions, but the range of possible locations is still pretty small. – Javier Sep 15 '16 at 9:58
• By the way, electricity is simply the propagation of the field, not the electrons themselves in general. – Lelouch Sep 15 '16 at 14:41
• Electrons can be anywhere, but they're very unlikely to be anywhere that they're not supposed to be :) – tparker Sep 15 '16 at 21:31

I hope I understood your question correctly.

First off, lets consider a circuit, just a simple circuit that has a battery and an LED connected by wires. The LED glows because the electrons moved from one terminal of the battery to the other terminal. That's what you already know. Particles will flow if there's a potential difference affecting them.

Now lets come to the observing an electron part. Usually when they say "observing a particle" it means that you observe it using EM waves. EM waves have energy that they can impart to the particles under observation. Since, electrons have such low mass they can easily absorb the tiny amount of energy to make transitions in the orbitals that they're moving around the nucleus. (By Heisenberg's uncertainty principle either the momentum or the position will change upon observation).

In a circuit the electrons are jumping atoms due to a potential difference. You don't need to put any "observational energy" to make them move. That means you don't need dwarves looking at them to make them move. They're moving because they're compelled by the "power of potential difference".

To clarify in one line --- When you see something that small it mean you're putting energy into it changing it's position. But to move that particle you don't always need to "see" it. It might be moving already due to nature.

P.S. I urge other users to correct me if I'm wrong instead of ridiculing. Thanks! :)

• Flag any offensive ridicule you get. My only modification would be to include references to resources at the level of the OP, so he/she can research it more. – user108787 Sep 15 '16 at 11:39

Electrons can be everywhere in that they have a non-zero probability of being anywhere until observed. See any standard quantum mechanics textbook on this one.

However in a wire, the electron has an infinitesimally small probability for being outside the wire. One can think of the electron in a wire as a wavefunction subjected to a potential. By solving the Schrodinger equation with this constraint, we are left with a solution for the wavefunction from which we can extract information such as the probability of the electron being found anywhere in a small region of space within the wire or the average momentum of the electron etc Basically the Schrodinger equation gives the time evolution of the state of the electron just as the classical analogue Newton's second law would have done. From knowing how the wavefunction evolves, for example, we can predict where it will have the highest probability of being in the wire. This is perhaps what is interpreted as the electric current in the wire.