Why Are There Opposite Charges?

Why are there opposite charges? According to at least one string theory, a charge is caused by a string wound around a cylinder that contains a hidden dimension through its cross-section. If the string is wound in one direction, the charge is positive. If it is wound in the opposite direction, the charge is negative. Below is a diagram of the model:

The problem with this model is you have a hidden dimension and a string. This creates a greater burden of proof for the physicist. The physicist must now discover strings and extra dimensions. Good luck! Plus it looks man-made and not natural. Finally, it is not intuitive or obvious why a plus charge is attracted to a minus charge or why same charges repel.

Question: why is the string and extra dimension necessary? Below is a model where the extra dimension and string are removed. It is simply a point with arrows that represent field lines. When the arrows go in, the charge is positive; when the arrows go out, the charge is negative.

The diagram below shows two negative particles. Notice how the arrows (field lines) between them look like they are pushing against each other--like two rivers flowing against each other. This is consistent with the fact that they repel each other.

In the next diagram we have two positive particles. Notice how the field lines (arrows) between them look like they are moving away from each other. This is consistent with them repelling each other.

The final diagram below shows a positive particle interacting with a negative particle. Notice how the arrows flow in the same direction. They don't push against each other, nor do they move away from each other. This is consistent with attraction.

As you can see it is possible to build a more intuitive model that demonstrates opposite charges without increasing our burden of proof, i.e., without adding extra dimensions and strings.