# I Water waves are waves because we can see them moving up and down, but electron waves?

#### LSMOG

If we say electron behaves as wave, does this mean if we were able to see an electron, we would see it moving up and down?

Related Quantum Physics News on Phys.org

#### Drakkith

Staff Emeritus
2018 Award
Nope. These waves are only "probability waves", meaning that all the wave-like properties determine the probability of the electron being within some location when you observe it. Once you observe it, the wavefunction "collapses" and the electron appears in a single spot like a particle. If you follow up your first observation with subsequent ones, you will not find the electron moving or oscillating up and down. What it will actually be doing depends on the situation.

#### Jilang

No, the likelihood of finding it at a certain place will go up and down.

#### Drakkith

Staff Emeritus
2018 Award
No, the likelihood of finding it at a certain place will go up and down.
Not true. Unless the properties of the system change, then the probability of finding the electron at any location remains the same as before. As an example, if I observe that an electron exists around an atom in a specific location, call it X, the probability of it being at position Y remains the same as before unless I modified the system (the atom and electron in this case) by observing it, perhaps by exciting the electron to another energy level.

#### Jilang

Not true. Unless the properties of the system change, then the probability of finding the electron at any location remains the same as before. As an example, if I observe that an electron exists around an atom in a specific location, call it X, the probability of it being at position Y remains the same as before unless I modified the system (the atom and electron in this case) by observing it, perhaps by exciting the electron to another energy level.
Agreed. More akin to a standing wave, which waves in space but not in time. A confined particle has that nature.

#### anorlunda

Mentor
Gold Member
Electrons make Interference patterns like photons do in the double slit experiment. That implies some wave like properties.

#### Mentz114

Gold Member
Electrons make Interference patterns like photons do in the double slit experiment. That implies some wave like properties.
It implies wave-like properties of the probability amplitude distribution of position (or momentum). In a guide wave theory the electron is a point, not a wave.

Interference happens in a phase space unlike classical light.

"Water waves are waves because we can see them moving up and down, but electron waves?"

### Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving