Would electric field exist if there were only one type of charge?

AI Thread Summary
The discussion centers on whether an electric field can exist with only one type of charge. It is argued that electric fields require bipolarity, as isolated charges do not create fields unless separated. The responses clarify that the existence of an electric field is independent of the types of charges present. The conversation also touches on the implications of having only one type of charge in relation to Gauss's Law and the nature of the universe. Ultimately, while the scenario of a single charge type is theoretically interesting, it does not reflect the actual observations of nature.
navneet9431
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Homework Statement
If there were only one type of charge in the universe, then:

ϕ=∮E⋅∂A≠0 on any surface.
ϕ=∮E⋅∂A=0 is the charge is outside a surface.
ϕ=∮E⋅∂A will not be defined.
ϕ=∮E⋅∂A=qϵo if the charge is inside the surface.
Relevant Equations
Gauss Law
Φ=∫E⋅dA
The answers were given as being the second and the last option.
I believe the answer is incorrect, reasons:

  1. The answer assumes that electric field will exist .
  2. But this is not the case , until and unless there is a bipolarity there cannot be an electric field ( in case of isolated charged objects, the field exists because the bipolarity is separated by a distance ∞ )
  3. This integral will result in a constant 0 as the electric field will be zero.(all cases)

I want to know if my reasons are correct or not if not then why is the given answer correct or wrong and what should be the correct answer?
 

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Your reasons are not correct. The given answers are correct if you change the last one to "inside" instead of "outside" (otherwise the second and the last are obviously in disagreement).

The existence of the electric field has nothing to do with the actual existence of charges or particular types of charges.
 
Orodruin said:
Your reasons are not correct. The given answers are correct if you change the last one to "inside" instead of "outside" (otherwise the second and the last are obviously in disagreement).

The existence of the electric field has nothing to do with the actual existence of charges or particular types of charges.
So is it correct to assume this world made up of only one type of charges(electrons)?
Would the assumption that only one type of charges exist not affect Gauss Law?
 
navneet9431 said:
So is it correct to assume this world made up of only one type of charges(electrons)?
Would the assumption that only one type of charges exist not affect Gauss Law?
It depends on what you mean by "correct". It is not compatible with what we actually observe from Nature. However, there is absolutely nothing wrong with theoretically considering such a situation.

No, not at all.
 
Orodruin said:
if you change the last one to "inside" instead of "outside"
Thanks for your explanation!
But,What is meant by this line?
 
Your original post read (at least on my screen)
ϕ=∮E⋅∂A=qϵo if the charge is outside the surface.
It should be "inside" as it is now.
 
Just a remark. If there were only one kind of charge in the Universe, would the Universe not necessarily have a net charge? If this charge is localized, then the question can be answered by considering a Gaussian surface that encloses all, some or none of the charge. If the charge is (perhaps uniformly) distributed over the entire Universe, see
https://www.physicsforums.com/threads/breakdown-of-gauss-law.926835/
 
kuruman said:
Just a remark. If there were only one kind of charge in the Universe, would the Universe not necessarily have a net charge? If this charge is localized, then the question can be answered by considering a Gaussian surface that encloses all, some or none of the charge. If the charge is (perhaps uniformly) distributed over the entire Universe, see
https://www.physicsforums.com/threads/breakdown-of-gauss-law.926835/
Yes, but we are clearly not describing our actual universe here. I do not see a self-contradiction in having a total net charge in Maxwell’s electromagnetism.
 
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