# Does the attached figure show how particles produce wave?

I have always been trying to understand and visualize what wave is and how it's been produced. I guess what ordinary people know about wave is just a particle moving up and down but last week I came across this image that titled “how particles produce Wave”. According to this image, the interaction between particles and how close they got produces wave, in other words, a single particle cannot produce wave.

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I really want to know the credibility of this image and if that is true or not. Now if this image is true, another question is why atoms in matter doesn't produce any wave but photons do?

I always thought that wave is produced by swinging a single particle but that vision never convinced me and I knew something is wrong. I want to know if waves are produced by a collective movement of particles (not a single particle). Is this always the case; is any wave in the universe produced this way?

• As a visual example of different wave motions, see this page: < acs.psu.edu/drussell/demos/waves/wavemotion.html > – AlQuemist Dec 15 '15 at 10:52
• @PhilosophiæNaturalis , I dont understand why a matter wave needs to have large number of particles, A single particle would have both particle and wave like properties. right? – Courage Dec 15 '15 at 10:57
• Since I haven't studied physics and all my knowledge is from school and reading articles, I always thought that wave is produced by swinging a single particle but that vision never convinced me and I knew something is wrong. But now I want to know if waves are produced by a collective movement of particles like you said. But I'm a bit confused, is this always the case? I mean is any wave in the universe produced this way? – xbmono Dec 15 '15 at 10:57
• But now I want to know if waves are produced by a collective movement of particles. The answer is yes. is this always the case? When would it not be? – Steeven Dec 15 '15 at 11:00
• @Vishwaas So how a single particle can behave like a wave if it's not interacting with any particle? – xbmono Dec 15 '15 at 11:02

I guess what ordinary people know about wave is just a particle moving up and down

I do not agree with this. One of the most common examples introduced while teaching waves is springs and ropes. And, in general, many learn about transverse and longitudinal waves on these media. That is, a wave is not necessarily an up and down motion.

I really want to know the credibility of this image and if that's true or not.

What you see in this animation is that, some particles are orbiting around a grid of points with the same period. However, since they are out of phase their collective movement creates the wave appearance. By changing the the speed of particles or adjusting the phase difference one can create many different appearances.

why atoms in matter doesn't produce any wave but photons do?

Atoms in matter produce waves and these are called phonons. Free electrons in metals create collective movements and these are called plasmons. There are more "wave-like movements" in solids which I cannot really name.

Please read the wikipedia article for more quasi particles in solids some of which related to "waves" in solids.

Here are two examples of "side ways" waves

This is a very nice illustration, giving that 3D feeling of a wave.

Does the attached photo show how particles produce wave?

Well, apparently yes. We can agree that what we see is an illustration of a wave, right? And it is composed solely of particles moving. So, that answers your question: This animation does show how particles can produce a wave.

The word can is important, because you seem to think that this cannot be right maybe because you have seen other examples elsewhere and think that there must be one single truth model of a wave. But waves are many things. This is just one example. All you need for a wave is the wave motion of some kind of pulse. They could also be

• mechanical waves (a jolted robe),
• pressure waves (sound moving through air),
• electromagnetic waves that don't even have a medium and therefore no particles to illustrate it like your animation,
• etc.

a single particle cannot produce wave.

Your animation illustrates nicely how a wave is formed when the pattern is right. When a water wave moves, it means that one water particle is moving and pulling the next water particle along with a slight delay, which then pulls the next water particle along and so on. One particle alone cannot constitute a wave.

Now if this image is true, another question is why atoms in matter doesn't produce any wave but photons do?

Why should atoms in matter do that? You want motion of particles in a fitting propogating pattern to cause a wave. Why should still atoms in matter have anything to do with waves?

• My questions is more about photons and electrons in quantum world and not mechanical waves. So now we know that light in different color has different wave length and frequency and so as X rays UV etc. Is this frequency we are talking about the same collective movement of photons for example? and the wave length is the distance of between two groups of particles just like the image – xbmono Dec 15 '15 at 11:09
• @xbmono No. your question is a about a classical wave. The quantum mechanical wave is expressed in a probability amplitude, not a change in energy of mass or a motion of an underlying substructure. – anna v Dec 15 '15 at 11:15
• @xbmono: The question as it stands is centred on classical mechanical waves. You should not expand the question in comments. Otherwise, answering the question becomes very difficult, or impossible. – AlQuemist Dec 15 '15 at 17:34
• @Philosophiae but in my question I clearly mentioned 'photons' and 'particles' I thought that tells what field of physics I am asking about. By the way, your link you sent is very good. Haven't read all of it though – xbmono Dec 15 '15 at 21:26
• @xbmono: All right; but the context which you provide for your question is completely related to classical mechanics. The picture also refers to mechanical waves. You have merely mentioned 'photons' in a part of your post, along with other questions which are related mostly to mechanical waves in matter. So, I'd say that your post does not convey what you mean -- perhaps, you should revise it and focus on the question you had in mind. I'd suggest reading more about waves and then, asking a better question. – AlQuemist Dec 16 '15 at 9:51