Why do electromagnetic fields exist where there is no matter

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Discussion Overview

The discussion revolves around the existence of electromagnetic (EM) fields in regions of space devoid of matter, exploring the nature of these fields, the forces between charged particles, and the underlying reasons for the behavior of these forces.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions the definition of an EM field as described by Wikipedia, noting the absence of charged objects in certain regions of space.
  • Another participant argues that the force between charged particles exists regardless of distance, suggesting that an EM field is present even in empty space due to the infinite range of electromagnetic forces.
  • A request for a simpler explanation of why charged particles experience forces at a distance is made, indicating a desire for clarification on the concept.
  • Responses highlight that the observed behavior of charged particles follows the inverse square law, but do not provide a deeper understanding of the fundamental cause of electromagnetic forces.
  • Participants express uncertainty about the fundamental nature of EM forces, acknowledging that while calculations can be made, the underlying reasons remain elusive.
  • There is a philosophical reflection on the implications of understanding the fundamental causes of forces, with one participant pondering the potential impact of such knowledge on human evolution.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and curiosity regarding the nature of EM fields and forces, with no consensus on the fundamental causes of these phenomena. The discussion remains unresolved with multiple viewpoints presented.

Contextual Notes

The discussion highlights limitations in understanding the fundamental causes of electromagnetic forces and the implications of these forces in the universe, without resolving the complexities involved.

Intropersona
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Wikipedia define EM field as "a physical field produced by electrically charged objects"

But there are no electrically charged objects in between cosmic entities and yet Wiki states "The electromagnetic field extends indefinitely throughout space".

What am I missing here?
 
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Consider that two electrically charged particles will experience a force due to their charges no matter what the distance is between them, with the strength of this force inversely proportional to the square of the distance between them. In other words, it scales at 1/r2. The range is infinite. So no matter where in the universe one of them is placed, an EM field will exist. So even if intergalactic space was completely empty (which it isn't) there would still be an EM field because matter exists somewhere in the universe.
 
Drakkith said:
Consider that two electrically charged particles will experience a force due to their charges no matter what the distance is between them

Can you please explain simply why that is so?
 
Intropersona said:
Can you please explain simply why that is so?

It's an observed fact. Charged particles are observed to either repel or attract each other. The strength of the force follows the inverse square law, which I gave above. What would you like explained?
 
Drakkith said:
It's an observed fact. Charged particles are observed to either repel or attract each other. The strength of the force follows the inverse square law, which I gave above. What would you like explained?

Why are there EM forces linked?

Wiki just says: an inverse-square law is any physical law stating that a specified physical quantity or intensity is inversely proportional to the square of the distance from the source of that physical quantity.

That's just saying how the strength of the force is to be calculated? That doesn't tell me much about why the forces of each atom are linked?
 
Intropersona said:
That doesn't tell me much about why the forces of each atom are linked?

You won't find an absolute answer. We know how to calculate the strength of the force, but we don't know the fundamental cause of the EM force or any of the other fundamental forces.
 
Drakkith said:
You won't find an absolute answer. We know how to calculate the strength of the force, but we don't know the fundamental cause of the EM force or any of the other fundamental forces.

Well, that seems quite a predicament for the cosmic evolution of human beings now isn't it. If we were to know... what could we do with that knowledge?
 
Intropersona said:
Well, that seems quite a predicament for the cosmic evolution of human beings now isn't it. If we were to know... what could we do with that knowledge?

Who knows? Perhaps nothing, perhaps something.
 

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