How are Electromagnetic waves created?

I want to know what happens at the micro level and why they are formed in "waves" & how do they propagate?

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vixra.org/abs/1712.0598
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If you look into Maxwell's equations (especially the Maxwell-Ampere and Maxwell-Faraday ones) ,you'll see that the propagation of an EM wave depends on itself : the propagation of the "electrical" component depends on the "magnetic" component and vice versa.
The variation of one side induces the variation of the other and so on,which is why they can propagate through nothing.

>through nothing
Well that's one retarded way to put it,I meant to say "through an empty space"

>through nothing
>Well that's one retarded way to put it,I meant to say "through an empty space"

But you're saying the same thing. There is no such thing as "empty space". It's a pressure difference.
The "waves" are perturbations of magnetism. There can be no electricity without magnetism and vice versa. Basically the electricity is "already there" in the wires/motor/generator it's just getting it to move in oscillations with magnetic fields. Nothing is actually moving except the magnets (and magnetic fields).

As noted, it's just a self-sustaining oscillation of E & M fields.
If you alter an electric field it induces a magnetic field, and vice-versa.
At the micro level, how do you get this started?
Pick up an charged object. Anything! A single electron will do if you have tweezers with very fine tips.
Now wave your hand back and forth rapidly. If you can move your arm around 1E12 times/second the FCC will descend on you for unlicensed broadcasting. At 3.4E14 cycles/second you'll see a red glow. Go faster and the light will turn blue.
That's all a radio transmitter is -- a method of kicking electrons back and forth very rapidly.

wrong about most of this
>how do they propagate
When travelling through media such as air, glass, or vacuum, light rays travel in straight lines through the medium, but refract and change their path at the interfaces between the media, according to Snell's law:
[eqn] n_1 \sin \theta_1 = n_2 \sin \theta_2 [/eqn]
The n_1 and n_2 are the refractive indices of two media present ([math] n_{air} \approx n_{vacuum} = 1 [/math], [math] n_{glass} [/math] varies depending on composition but may be more like 1.5) and the angles [math] \theta_1 [/math] and [/math] \theta_2 [/math] are relative to the normal vector of the surface swept out by the interface. This is the basis of how eyeglasses and other glass lenses work, or why an object at the bottom of a pool looks distorted and to be in a different location.
If the angle is shallow (large) enough and the light is propagating in the higher refractive index medium of the two, a total reflection can occur at the boundary instead of transmission/refraction. This is how waveguides like fiber optics work. In reality, refraction can also depend on the frequency (color) so that different frequencies refract at slightly different angles. This is what causes optical prisms to separate white light into a rainbow.
Of course photons will do many things at the quantum level, especially interact with electrons and drive them to excited states when the electron absorbs the photon and its energy, before radiating a photon at a later time and decaying back to a lower energy state. This can be seen from emission spectra of various gasses, such as glass tubes filled with hydrogen or helium.
At intermediate scales such as in waveguides, Maxwell's equations are still often used to describe the transverse and longitudinal resonance modes, both electric and magnetic, of the light source in response to the waveguide. In general this is pretty complicated and depends on the geometry and constituent frequencies.

>wrong about most of this

nice refutation, mathematician.

>When travelling through media such as air, glass, or vacuum, light rays travel in straight lines through the medium, but refract and change their path at the interfaces between the media, according to Snell's law.

Well that's just a fine and dandy description, but what about explanations?

>all this gibberish explaining how light refracts and then just going back to "well at the quantum level" yada yada, "electrons, excitation ".

Higher frequency(of light)=more capacitance because more waves are taking up the same spacial foot print. Glass is a dielectric capacitor. When the light passes through glass, the large wavelengths on the red end of the spectrum have lower frequency and therefore don't pass through as much glass. The blue end has higher frequency wavelengths and therefore passes through more glass which is why it gets "diffracted" more (diffraction is the wrong term since the light actually slows down because it is being stored by the capacitor that is the glass.

>That's all a radio transmitter is --
>a method of kicking electrons back and forth very rapidly

Perturbations.

>nice refutation
What? That post was garbage schizo ramblings.
>The "waves" are perturbations of magnetism.
What makes a magnetic field more fundamental than an electric field? It's an electromagnetic excitation and both fields are needed.
>Basically the electricity is "already there"
No, unless you mean the existence of electrons. The photons and their effect aren't there until they are.
>in the wires/motor/generator it's just getting it to move in oscillations with magnetic fields
Now you're talking about currents and applied fields in conductors instead of light. Anyway, the current flowing in a wire is due to the electric field that propels electrons forward, not the magnetic field that deflects moving electrons at right angles relative to their movement and imparts no energy
>Nothing is actually moving except the magnets
Photons DO move through space and transparent materials.

>Well that's just a fine and dandy description, but what about explanations?
I tried to give examples and a simple explanation of the formulas. What more do you want?
>When the light passes through glass, the large wavelengths on the red end of the spectrum have lower frequency and therefore don't pass through as much glass.
If that were true, the glass would appear to be blue or violet itself. The fact that glass appears clear means that all visible wavelengths transmit through it with about the same probability close to 1.
>The blue end has higher frequency wavelengths and therefore passes through more glass which is why it gets "diffracted" more
Transmission through glass or large interfaces is not diffraction. Diffraction requires a geometrical obstruction on the order of size as the wavelengths of the light (so ~10^(-6) m or smaller). Diffraction and refraction are distinct phenomena.

Thank you for the explanation :)

Rubik's scissors operate to cut the flux bundles away from their sources

see here for more on Rubik's scissors
>The General Relevance of the Modified Cosmological Model
>vixra.org/abs/1712.0598

>What? That post was garbage schizo ramblings.
So it should have been easy to refute the points made.

>What makes a magnetic field more fundamental than an electric field? It's an electromagnetic excitation and both fields are needed.
Correct, should have added that.

>No, unless you mean the existence of electrons.
They don't exist. There is not some magical fairy tale unicorn particle that just magically appears out of nowhere. It is electric and magnetic fields working AS ONE not "this one and that one". These do not spawn arbitrary "particles", they cannot do so by the very nature of how they work. One may dominate over the other in different configurations and this will produce different effects, but they are still ONE thing and ONE thing only.

>The photons and their effect aren't there until they are.
If you can point to me one place in the universe where light does not reach then I will believe this statement. No a "blackhole" doesn't count because it's still theoretical.

>Photons DO move through space and transparent materials.
There is no empirical evidence of a photon particle.

>I tried to give examples and a simple explanation of the formulas. What more do you want?
"I tried to give examples and a simple explanation of human descriptions. I can do math and at the same time think the universe does math as I do"

>If that were true, the glass would appear to be blue or violet itself. The fact that glass appears clear means that all visible wavelengths transmit through it with about the same probability close to 1.
Look at pic related. Do you see how the red is bigger than the violet? What do you think is going to happen when a combination of all these colors hits a dielectric capacitor, keeping in mind that light is made of what now?

>There is no empirical evidence of a photon particle.
There IS evidence photons travel as pulses and ultimately discrete units.
>They don't exist. There is not some magical fairy tale unicorn particle that just magically appears out of nowhere. It is electric and magnetic fields working AS ONE not "this one and that one". These do not spawn arbitrary "particles", they cannot do so by the very nature of how they work. One may dominate over the other in different configurations and this will produce different effects, but they are still ONE thing and ONE thing only.
this is gobbledygook
>human descriptions
Snell's law is empirically verifiable fact, user. Go back to intro to philosophy and argue in favor of solipsism you nerd.
>Do you see how the red is bigger than the violet? What do you think is going to happen when a combination of all these colors hits a dielectric capacitor, keeping in mind that light is made of what now?
Gobbledygook. Explain what the fuck you are saying with math, without just sperging out a bunch of more bullshit terms with no connection.

Electrical wavefield running down a cable. Hits the end of the cable. Sufficent power levels push the em wave into the free space media. Its just the em wave propogating along the cable until it gets pushed off the end to travel as a waveform, leaving the oscillating electrons behind.

Or similar. Laymens terms. Happy to be corrected.

The design of the cable end is important as it determins the size and shape of the field of em waves as they propogate into the free space media.

To put it better maybe... The EM waveform is already there, travelling along on the outside of the cable not contained within it like the electrons are. When the end of the cable is reached the signal leaves the cable entirely as a wave form.

When this wave form hits the end of the cable it keeps going, and when it passes by any recieving objects the energy in the waveform will induce movement in electrons in other wires it passes by. Or antennas.

The shape of the waveform is primarily determined by the origin of the signal, and secondarily propogates forth in a shape and direction determined by the antenna.

>If you look into Maxwell's equations (especially the Maxwell-Ampere and Maxwell-Faraday ones) ,you'll see that the propagation of an EM wave depends on itself : the propagation of the "electrical" component depends on the "magnetic" component and vice versa.

This is the brainlet response. Here is the real redpill.

There is no such thing as an electromagnetic wave. There is no medium so there is no true propogate not. Faraday's law and amperes law do not predict an electric field creating a magnetic field since both laws and fields use the immediate value. There is no causality .

What creates changing magnetic and electric fields is changing charges and currents.

You can read the work of jefinmenko to uncuck yourself.

Take the maxwell equations for the vacuum:
[eqn]\vec{\nabla} \cdot \vec{E} = \frac{\rho}{\epsilon_0}[/eqn]
[eqn]\vec{\nabla} \times \vec{E} = - \frac{\partial \vec{B}}{\partialt}[/eqn]
[eqn]\vec{\nabla} \cdot {B} = 0[/eqn]
[eqn]\vec{\nabla} \times \vec{B} = \mu_o \vec{j} + \mu_0 \epsilon_0 \frac{\partial\vec{E}}{\partial t}[/eqn] and then take the curl of the curl of the magnetic field to proove that it obeys a wave equation:
[eqn]\left( \partial_x ^2 - 1/(c^2) \partial_t ^2 \right) \vec{E} = \vec{0}\/eqn]
same goes for B.

of course using the continuity equation:
[eqn]\frac{\partial \rho}{\partial t} + \vec{\nabla} \cdot \vec{j} = 0[/eqn]

You are beyond retarded, you definitely havent never taken a physics class in your life let alone a complete education.

>There is no medium

Do you troll sir. If a signal is moving through something then there is a medium. It is a requirement. The signal must have a path.

If you are trying to say that you have been taught that the electrons still transmit the signal then I can accept that however I have been taught the practical application as it applies to the propogation of an em wave form through the free space medium. Air in other words, Im not sure how it applies in a vacuum outside earths radiation shield that would be fascinating knowledge I think.

I was taught that free space electrons are more resistant than those in copper wire but frequencies which propogate easily through the free space media can be exploited to contain most of the power in the em wave.

>Do you troll sir. If a signal is moving through something then there is a medium

Reread the post. There is nothing traveling. There is no wave. There is no propogation. There is a delay because of the finite speed of light, but nothing else. A charge or current is time varying and can make a charge or current vary in time somewhere else.

You can call it a wave equation, but it's merely a partial differential equation that's has sines and cosines as solutions. There is no wave. Also the equations in the end only depend on the electric or magnetic field and there is no dependency between them.

Es don't make Bs and neither propogate.

It is crowded here, i can help.
whiy are they waves.
Ok OP, lets get this straight. you have a electromagenetic field. Two dimensions one electric one magnetic three espatial dimensions and my friend the fucking time. Ok. this field exist in the whole fuking universe because it is the boss. And in the classical interpretation, it always fullfill the Maxwell ecuations. So the wave is a perturbation of the electromagnetic field that is compatible with the maxwell ecuations so if you make the field oscilate in the proper way the wave simply appear. Why, because it is the oscilation that the maxwell ecuations allow any other result it is simply not allowed.
What happens physicaly.
When you are a seasoned scientist, you say it does not matter, it is a model you assume it works end of the story. For begginers that need something with more sustance, the waves can be produced in many ways as the models for the field get more and more detailed and it goes far beyond what i can explain here. But the classic ecample is you have permanent magnet a you make the magnet spin you have a conductor and the electric field on the conductor starts to oscilate due to the induced current, then things get weird the electromagnetic field aroud the conductor starts to oscilate because the whole universe has to fullfil the maxwel equations and you can not have an oscilation of the field without making an oscilation that travel to the end of the world so the wave appears end propagates. Maxwell ecuations force the wave to do it there is not other solution for the field end of the story.

EM waves doesn't require electrons.
Look at an old-style light bulb. The air is pumped out so the filament doesn't burn.
There's a vacuum inside.
Yet you see the light -- which is an EM wave.

You can see other galaxies via visible light, x-rays, radio waves, whatever.
And we're separated from them by a billion light years of ridiculously hard vacuum.

Physicists USED to think light required a medium. It was called the luminiferous ether and remained even when there was no air present.
The ether (or aether) has been dead for over a century.
It doesn't exist.
There is no medium.
EM waves are called "waves" only because of the equations which describe them. They're not "disturbances" in an imaginary fluid. Changing E makes B and vice-versa (you don't need light to text this. Wires and a magnet will do.) and the energy moves right along at cee. Always at cee measured by any observer. Not cee with respect to a medium.

>Es don't make Bs

As I understand it the oscillations are created by moving a magnet through a conductive coil connected to wires, the magnetic field interacts with the electrons in the copper and causes them to flow. This always kind of smelled like bullshit to me but whatever, I could do my job no worries...

The medium determines the attenuation of the signal over time and through space. For high energy waveforms like light, which are also a particle like wtf (i grasp basic concepts like refraction to contain light within its medium and that even light has an em wave), but I dont really think of light as transmission of energy. Light suffers great rates of attenuation within the atmosphere. My knowledge base is built off atmospheric signal transmission though not a physics degree.

The assumption always was that there are more efficient waveforms or frequencies to use for transmitting energy through the atmosphere than those in the light spectrum.

But in a vacuum does light win?

I forgot to mention that the e and m have to be always at right angles to each other.

>this is gobbledygook
No it's a hardcore fact you moron. There is no "just electricity" and "just magnetism". It doesn't exist you idiot.

>Snell's law is empirically verifiable fact, user. Go back to intro to philosophy and argue in favor of solipsism you nerd.

It's a comparison of ratios, it doesn't explain what is actually happening. The light slows down, to measure it and see how fast it slows down and how much it bends etc. doesn't explain why it's actually happening.

adding that the speed of light is a rate of induction of EM.
these niggas have it. Light and electricity doesn't move nor is it emitted. This is not even a new idea, Maxwell, Faraday, Oliver Heaviside, Steinmetz, Tesla and arguably even Einstein knew this.

The atmosphere absorbs different frequencies with varying effectivenesses. X-ray and a lot of UV astronomy can't be done from the ground because those wavelengths are almost totally absorbed.
Air is pretty transparent to visible light. That's why it IS visible light. Our eyes have evolved to make use of the waves which get through.

NOTHING is absorbed by passage through a vacuum. Without atoms in the way, there's nowhere for the energy to go. Photons of all frequencies and wavelengths can go a billion light years.

Light is definitely transmission of energy. Every kid has fried ants with a magnifying glass. A radar technician once notice that a chocolate bar in his shirt pocket melted. Out of this came the microwave oven. Energy from the magnetron vibrates water molecules in the food. That's heat, produced directly, without having to apply fire or steam or hot air.

Moving a conductor through a magnetic field induces an electric field. It pushes on everything, but the copper atoms are locked in place whereas the electrons (relatively) free to move.
The copper isn't even needed. If you build a vacuum tube with the electrons flowing through nothingness, passage through a magnetic field will jerk them to one side. Electron microscopes use magnetic fields to form immaterial lenses to focus and scan the beam. It's not BS.

>Changing E makes B and vice-versa (

No they do not. Equality does not imply causality. It's logically impossible for something to be made by the thing that it creates itself.

Charges and currents make Es and Bs. The relationship between Es, B's and Qs and J's is functional causal and does not violate logic.