how can an electron be a particle and a wave?

Question

I am reading physics of the impossible by Michio Kaku. He says that the Schrodinger equations give the probability of finding an electron at a point. He also says that when a single electron is passed through a tube it comes out the other end in concentric circles like a wave. So, maybe I am misunderstanding...Doesn't the Schrodinger wave equation mean that the electron is a single particle and the equation gives the probability of finding that particle in a place and time? Why does the electron still leave marks as if it were a wave?

Answer 1

Since an electron has a charge, it has an electric field surrounding it. As it moves the field disturbs the particles in the air around it, creating the "marks" it was talking about. I hope this helps.

Answer 2

Afaik, no-one really understands wave-particle duality. It's just the way the universe works!





The wave stays until you observe it, then it collapses to a particle. When you're doing the maths to explain what an electron is doing, you use the waves. When you look at it, it drops to a particle. The electron comes out of your tube in a wave, but if you put a screen somewhere to measure it you'll only get one spot from the electron (that's the particle), the probability of where that spot will be is determined by the wave.





You will get what looks like a wave if you pass lots of electrons through the tube. The probability of each electron hitting the screen is described by the wave mechanics, and the brightness on the screen is determined by the number of electrons - bigger wave amplitude at a point = more electrons will land there.





It's exactly the same effect for photons of light. You observe one photon on a CCD say and you get one spot. You observe loads of photons and they make a wave pattern - the wave pattern is the probability of the photon ending up there. If there's high probability (big wave), lots of photons go there and it looks bright and vice versa for the dark.

Answer 3

I remember my professor telling me in lecture that the Schrodinger equation gives legal quantum states. I never used the actual equation to do any calculations, but understanding it can be just as powerful:



("Hamiltonian Operator")*("wave function") = ("wave function")*("Total Energy")

(mentally replace the words in quotes with their corresponding Greek symbols)



Now, what the equation means conceptually is that solving for the wave functions gives us four legal quantum numbers: principle quantum number (QN), angular momentum QN, magnetic QN, and spin QN. So yes, knowing these quantum numbers will tell you a lot about electron configuration. I am not sure what your Chemistry background is, but I am sure you have or will learn about p shells, and s shells and all that fun stuff... An electron shell is the region in space where you can find an electron 90% of the time.



The equation in general is important because it proves that the electron behaves both like a particle and a wave and that energy is quantized.



As for your confusion concerning how an electron can be both a particle and a wave, there is no simple and straightforward answer. The way I understand it, is that an electron cannot be both things at the same time. It acts like a wave when we shine a light on it (aka when we try to LOOK at it, so to speak), but it also has the capacity to act like a particle when we turn off the lights and focus our attention on something else.



If you are really interested in this, I recommend reading Feynman's Lecture on the subject of quantum mechanics (just google "feynman's lectures"). He explains it very well in his book.

Answer 4

The electron can be considered as both a wave and a particle hence wave particle duality, the Schrodinger wave equation has to consider the position of the electron as a probability because until it is observed it acts as a wave rather than a particle. the act of observing the electron changes its properties because to observe it we must 'bounce' a photon off it.

Answer 5

I had a similar question when my professor put it in very simple terms....

Before getting inside the chapter..remember that according to the dual nature theory we "assume" that a fundamental particle can act as a particle as well as a wave...

You see there are some proofs which can be proved when you consider them as particles...while others can be proved only when you apply wave equations....

Now talking about Shrodinger equation gives the probablity of finding an electron in an "area" of a shell of an atom...so...if you look at the shapes of the shells of an atom....for example the s shell...which is spherical...the probability says that the maximum chance of finding the electron is on the outer curve of the sphere....it does not mean that the electron is leaving a spherical wave-front sort of thing at the place....dont confuse the probable area of finding the electron with the wave of an electron...

Answer 6

Neither. Waves and particles are models that can be applied to describe physical systems and processes. There are no perfect point particles in existencem, though we like to think there are because they are intuitively appealing. In fact, aspects of both wave models and particle models can be applied to the actual behaviour of electrons.

Answer 7

when you observe the electron as if it were a wave it behaves like a wave, and if you observe it as if it were a particle it behaves like a particle. people used to think that it "chooses" to be a wave or a particle, and many experiments have been done to try to "trick" the electron into behaving the wrong way. these have repeatedly failed though, and it remains that no one completely understands how it can be a wave and a particle at the same time.

Answer 8

Particle and wave are just models of thinking we use to describe and explain atomic and subatomic phenomena. In one experiment, electrons can be show to have wave properties (slit experiments) and we use wave theory and wave math to explain; in another experiment they can be shown to have particle properties and we use particle theory and particle math to explain. No single experiment can show both wave and particle properties simultaneously. If it were possible for us to go down to subatomic level and actually see electrons we might not even see waves or particles but just strange things that we might never understand because they might look like things we have never seen. We just use our ideas of waves and particles to explain how electrons behave.