# What is the underlying phenomenon of waves?

• B
• accdd
Planck's law states that energy is radiated away in waves. This law can be used to calculate the energy of an oscillating system.The energy of an oscillating system is proportional to the square of the amplitude of the wave.In summary, heat diffusion is caused by randomly moving particles. There is a connection between the diffusion equation and the statistical motion of particles. Waves are similar to heat diffusion in that there is a connection between the diffusion equation and the statistical motion of particles.f

#### accdd

Heat diffusion is caused by randomly moving particles. So there is a connection between the diffusion equation and the statistical motion of particles. Is there something similar for waves?

• Delta2
Heat diffusion is caused by randomly moving particles. So there is a connection between the diffusion equation and the statistical motion of particles. Is there something similar for waves?
You have Planck's law? Apologies this is level I so my ref was probably not very useful

• accdd
I changed the level to B, so I can understand

pinball1970
Sorry, maybe I misunderstood your message because I am using a translator.

Do you have an advanced level explanation? If yes please write it down, I will try to understand. Thank you.

• pinball1970
Particles in a matter wave (like sound wave, water wave) do not move completely randomly, rather they do ordered motion according to the wave motion. Clearly we can see that in a water wave.

• pinball1970 and accdd
What I mean is: is it possible to do something like this: "" -min 3- with waves?

Heat diffusion is caused by randomly moving particles. So there is a connection between the diffusion equation and the statistical motion of particles. Is there something similar for waves?
What kind of waves? One could discuss electromagnetic waves, or mechanical waves, and even with mechanical, we can discuss longitudinal waves, shear waves, surface waves, all of which depend on the media through which the waves propagate, the physcial (density) and mechanical (elastic) properties of that media. It's reflects the propagation or dispersion of momentum and energy from the excitation, a thermal pulse, a mechanical impulse, or a more sustained excitation, e.g., wind on the surface of water (or gas on a liquid). We could discuss acoustical sound waves, or ultrasonic waves, or shock waves, the latter being very complicated.

Some general mathematics of waves can be found here.
https://phys.libretexts.org/Bookshe...d_Oscillations_and_Waves_(OpenStax)/16:_Waves

A more focused discussion of surface waves might involve for example, the Korteweg–De Vries (KdV) equation, a mathematical model of waves on shallow water surfaces.
https://en.wikipedia.org/wiki/Korteweg–De_Vries_equation

• • pinball1970, Delta2 and accdd
What I mean is: is it possible to do something like this: "" -min 3- with waves?

Individual particles would still be moving randomly on a local basis, but you would have to add in some sort of forcing function to take care of the bulk movement as an ensemble.
So it seems particle interactions, which the video guy ( first time I have seen what he looks like ) ignores for the random walk., would have to be taken into account.

Astronuc.
The simplest wave equation is enough for me.

In classical physics waves require motions of substances, e.g. motion pattern of soils in different places for earthquake, sea water molecules for tsunami, air gas molecules for sound waves. Can you imagine waves without these substances motions ? ( QM waves including EM waves have another foundation.)

• Delta2
In classical physics waves require motions of substances, e.g. motion pattern of soils in different places for earthquake, sea water molecules for tsunami, air gas molecules for sound waves. Can you imagine waves without these substances motions ? ( QM waves including EM waves have another foundation.)
Electromagnetic waves are classical waves. There is nothing quantum about them until you want to quantize the EM field.

• malawi_glenn, Delta2 and anuttarasammyak
In context of OP question, I should have said that EM waves as well as probability amplitude in QM have no substances or media mechanical motion of which correspond to the waves.

• Delta2