Gauss' law for uniformly charged space

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Homework Help Overview

The discussion revolves around the implications of Gauss' law in the context of a uniformly charged infinite space. The original poster raises concerns about the apparent contradiction between the symmetry of the electric field and the application of Gauss' law, particularly regarding the flux through Gaussian surfaces in such a charge distribution.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • The original poster attempts to reconcile the electric field behavior in uniformly charged spaces with Gauss' law, questioning the implications of symmetry and the existence of such charge distributions. Some participants suggest the need for boundary conditions to maintain consistency with Gauss' law, while others reference related discussions on the topic.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of Gauss' law in relation to infinite charge distributions. There is acknowledgment of previous discussions on the topic, and some guidance regarding the necessity of boundary conditions has been provided.

Contextual Notes

Participants note the importance of boundary conditions and the behavior at infinity in the context of Gauss' law, indicating that these factors may influence the symmetry considerations being discussed.

Likith D
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the problem:
Say we have the entire space uniformly charged. Then, the E field experienced by any point is zero, from symmetry.*
But, it means that for any Gaussian surface, the flux though it is zero even though the charge enclosed is clearly not. Gauss' law seems to disagree with symmetry, but it also cannot 'therefore state' that such a charge distribution is not possible.** (only theoretically, if it should exist)*It is not 'not defined' for the same reasons E field inside a sphere of uniform charge distribution is not 'not defined'... so to say that it is not zero is to go against symmetry of space for that point
**Why would we not have 3d infinite charge distribution while we have 2d infinite charge distribution

attempt at solution:
So, I tried to use the fact that we already computed E field inside a spherical uniformly charged object and let the R tend to infinity which gives ; https://i.stack.imgur.com/N8dwe.jpg independent of radius of sphere.
which may or maynot be zero depending on center of sphere and the point, which makes it weirder... but I have tried integration to find the E field of a uniformly charged wire segment and made it's length tend to infinity to get an answer that agrees with Gauss' law (the same for a planar disc tending to infinite plane, works)... and uniformly charged space seems to be not following that...
Gauss' law just seems to disagree with uniform charged space
what do we make of all this? that Gauss' law is flawed?
If it cannot possibly go against symmetry, does it really imply that uniformly charged space is not possible?
 
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You need boundary conditions, i.e., a behaviour at infinity, that breaks the symmetry in order for Gauss' law to be consistent. This was discussed relatively recently in a featured thread. Boundary conditions that satisfy either translational or rotational invariance will break the other.
 
Last edited:
oh, I didn't notice we already had a thread regarding the problem... sorry about that!
 

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