# What causes electrons to move in wave form?

1. Jan 1, 2014

### John Light

Ok, so I have been searching around the internet for an answer to this and have not found anything besides the fact that electrons move in a quantum way, that is jumping from one place to another without passing through the space between those two places, which I am aware of. So the two main aspects of this question that I am confused about are:

1. What causes electrons to jump from orbit to orbit without any human influence like heating it when it is going around a nucleus?

and

2. After having read about the double slit experiment, I was confused about what the electron in the test was orbiting around if it was just an electron itself; how could it go about its normal movements without a nucleus as its center?

2. Jan 1, 2014

### bhobba

Check out:

In the double slit experiment with electrons its done with free electrons in a vacuum, like the electrons found in electronic valves in the hi-fi gear of audio nuts like me that prefer their sound, rather than new fangled transistors.

Thanks
Bill

3. Jan 1, 2014

### John Light

So, I know this may seem like an obvious answer, but what exactly is it that makes the electron move in the wave formation, or, more simply stated, makes it move at all?

4. Jan 1, 2014

### ZapperZ

Staff Emeritus
But what makes it moves in ANY formation, wave or not?

There is no answer to this. Just as there is no current explanation on why the charge of e is what it is, or why the maximum speed of light is a constant, there are things that happen because that's the way the universe is.

Now, if you are asking under what circumstances is the quantum mechanical description is more valid than the classical description, that we can answer. But we can't answer the "why, why, why" part.

Zz.

5. Jan 1, 2014

### DennisN

Not so obvious in my opinion.

To answer that with physics, we would need some kind of "subquantum" theory. The only answer I know of today would be "it's a feature of the universe/nature". We then make mathematical models of how these things work.

Conservation laws: http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html. If a free electron simply stopped by itself (without interacting with anything else), it would violate conservation of momentum and energy.

6. Jan 1, 2014

### John Light

Alright, thank you for that answer, I think it would be an amazing step in the world of physics if that question was answered. Thank you again though.

7. Jan 1, 2014

### John Light

On that last comment I was talking to ZapperZ

8. Jan 1, 2014

### John Light

And also apparently I was talking to DennisN, too. Sorry about that, I just hadn't read your comment yet, but thank you for it also, especially this part: "Conservation laws: http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html. If a free electron simply stopped by itself (without interacting with anything else), it would violate conservation of momentum and energy." This is really cool and I have never heard of it before, thanks! Also, how do you do that thing where you quote someone in blue?

9. Jan 1, 2014

### bhobba

Now you are asking why Quantum Theory which Zapper correctly points out there is no answer - its just the way nature is.

However much research has been done into its foundations, and these days its known its basically the most reasonable generalized probability model that can be used to model physical systems:
http://arxiv.org/abs/quant-ph/0101012

Maybe - maybe not.

Always remember if you explain something that explanation also depends on assumptions. Will they be more appealing than what they explain? Who knows.

Thanks
Bill

10. Jan 2, 2014

### vanhees71

An electron is an elementary particle. It can neither be described in all aspects as a classical particle nor as a classical wave.

In the non-relativistic approximation it can be described by Schrödinger's wave function, but that has not the meaning of a classical field. You cannot say that the wave function "is the electron" in the same sense as you say a position and momentum vector in classical mechanics of a point particle (i.e., a "small" macroscopic body) is the position and the momentum of this particle.

The wave function $\psi(t,\vec{r})$ gives the probability to find the electron at time $t$ in a little volume $\mathrm{d}^3 \vec{r}$ at a place $\vec{r}$ to be $|\psi(t,\vec{r})|^2 \mathrm{d}^3 \vec{r}$. In other words the probability distribution for the position of the electron is
$$P_{\psi}(t,\vec{r})=|\psi(t,\vec{r})|^2.$$
This is Born's rule and at the heart of the very foundations of quantum theory.

A lot of discussion occured in the last, say, 50 years about the interpretation of quantum theory. One is the minimal statistical interpretation, which just says that the meaning of the wave function is this probabilistic content. This means it refers to an ensemble of identically prepared electrons and doesn't say much about a single electron. According to quantum theory you cannot know more about a single electron as the probabilities for measuring certain observables (not only position but also momentum, angular momentum, etc.).

11. Jan 2, 2014

### John Light

Wow, this is an interesting thing to think about! Thanks for the insightful answer.

12. Jan 2, 2014