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If one creates an oscillating electric field and a magnetic field, transversal to each other, and oscillating at a given frequency belonging to the visible spectrum, and moving in a given direction of an observator, will an observer see the same as compared to the same experiment where he looks at the light ?

Said differently, is light nothing more than a pair of transverse electric and magnetic fields?
So would creating a pair of transverse electric and magnetic oscillating fields moving in a given direction be equivalent to create light?

Deschele Schilder
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Mathieu Krisztian
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An oscillating electric field and magnetic field propagates as light and Heinrich Hertz has already demonstrated that by creating radio waves in the laboratory.

So yes light is a pair of transverse oscillating electric and magnetic fields.

Lost
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To the question "is light nothing more than a pair of transverse electric and magnetic fields?" the answer is: "classically yes, indeed". However, these fields are a wave function, like Schrödinger's equation, that describes the probability of finding photons, the massless point particles that light consists of.

Deschele Schilder
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my2cts
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That's not the way you can create classical light waves. Both the electric and magnetic fields can't be made to vary in time independently.
It's the easiest just to let an electric field vary periodically in time at visible light frequencies. The magnetic field will automatically be created, according to Maxwell's equations.

A varying magnetic field would also create an electromagnetic wave, but that's much harder to realize because there is much less energy contained in a magnetic field.

In both cases (creating the varying fields) an electromagnetic wave will emerge.

So the answer is: No.

Deschele Schilder
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It can be hard to say what light really is. You are talking about the classical view of light. Descheleschilder's answer is correct. But if you look at a microscopic view of light, you need quantum mechanics.

This is like looking at what air pressure is. In a large scale view (classical), it is a smooth force that air exerts on the walls. But microscopically, it isn't smooth. It is individual air molecules bouncing off the wall. Each molecule gives the wall an individual kick. When you add up lots of these kicks, you get a smooth force. It is really the same explanation, but it looks totally different.

Light is the same. On a microscopic scale, light can be emitted by an individual electron in an atom, and absorbed by another electron in another atom. One atom gives another a kick. When you add up lots of atoms, you can see a smooth force that is described by an electromagnetic field.

An individual atom's worth of light has a name "photon", but that doesn't say what light is. A photon is sort of like a particle and sort of like a wave. For more on that, see my answer to How can a red light photon be different from a blue light photon?.

It can also get confusing if you take a careful look at the classical picture. What kind of thing is an electric field? See my answer to In what medium are non-mechanical waves a disturbance? The aether?

mmesser314
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