Four fundamental types of interaction or force can be used to describe the interactions of particles observed in nature: electromagnetism and gravitation. Their qualitative properties distinguish them.

One of the four can be attractive or repelling and is long-ranged. This force we call electromagnetism.

This force can interact with some particles. Some don’t. Some particles interact with others in different ways. Each particle is assigned a number. Zero if it doesn’t interact electromagnetically; nonzero if interacting, along with the magnitude that characterizes the strength of interaction. These particles can be divided into two groups so that opposites attract. Each particle is assigned a positive number and each particle is assigned a negative number in each group.

This is what an electric charge is. It’s that simple. We have a force law[math]F [math]

[math]q_1, [q_2[/math] represent the charges, and [math]F[/math] the electromagnetic force. These are the numbers that we assign to particles to make this equation true. That’s it.

If you look at physics deeper, you will see that the electric charge is created from asymmetry in the equations. This is called gauge symmetry. This framework will give you more insight into fundamental interactions. However, it doesn’t change the fact that electric charge is created because electromagnetic interaction is observed. There is no reason to believe that there should be an electric charge. This theory does not explain the origin of electric charges in particles.

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