Is wave a physical object or its just a model?
Have you ever surfed?
A physical wave is a physical wave and a model of a wave is a model of a wave.
This is an open question. To quote from Franck Laloë's Do we really understand quantum mechanics? Strange correlations, paradoxes and theorems:
Having trouble seeing how a wave function can be interpreted as a physical thing....it implies too many exotic attributes. By Occam's razor it is more efficient to discard a wave function as a physical object, IMO.
Is wind "just a model"?
Is "temperature "just a model"?
Is "resistance" just a model?
(About a zillion other things can go here)
If we say " the electron is a wave" does this mean an electron is travelling up and down like water?
No it does not mean that.
The electron is neither a wave nor a particle, it is a quantum object that displays wave-like or particle-like behaviour depending on context.
The position and momentum is described by a probabilistic function, which takes the form of a complex wave equation.
No "we" are saying that in the context of specific physical systems a wave function can be defined such that when specific operations are applied to it we get a range of values that describe the electron's behaviour that can be verified experimentally.
That's what "we" are saying.... but I don't want to speak for other people so "we" is just "me".
In a wave, lets say a string, we can measure the wavelength to be the distance between the two troughs. Then which points in an electron can we use to measure the trough if it is a wave?
Diffraction of electrons yields their wavelength. Just as in light.
You have seen electron microscope images?
Before thinking about an electron, you might want to analyse your example of a wave in a string. What is the wave as a "physical object" in this case? The string is physically a row of particles and each particle is moving up and down with simple harmonic motion, out of synchronisation with each other, such that particles a certain fixed distance apart are in synchronisation. Now, where and what is your wave physically in this case? You appear to have a sinusoidal wave propagating along the string, but is that really a "physical" thing or just an illusion caused by the vertical motion of each particle?
If you simulated a wave by, say, having sets of vertical lights in a long horizontal row and had the lights go on and off in a certain pattern, then you would see a wave appear to propagate. Is this still a physical wave or a simulation?
In other words, what actually is a wave physically?
As always contest is everything.
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