Evidence that the Universe is Electrically Neutral

Moneer81
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Hello,

Homework Statement



What evidence do we have to support the assertion that the universe is electrically neutral on large scales?

Homework Equations





The Attempt at a Solution



I know that gravity is the dominant force on large scales but what kind of evidence can we give to support that? Does it suffice to state that we have the same number of protons and electrons?
 
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Is the universe neutral?
If there was a uniform distribution of charge would you notice ? There would be no field and there is nothing outside the universe to compare the charge to.
What is the evidence that there is an equal number of e- and p+?
Just saying that there should be isn't enought - after all there isn't an equal amount of matter and antimatter
 
mgb_phys said:
Is the universe neutral?
If there was a uniform distribution of charge would you notice ? There would be no field and there is nothing outside the universe to compare the charge to.
What is the evidence that there is an equal number of e- and p+?
Just saying that there should be isn't enought - after all there isn't an equal amount of matter and antimatter

The universe is indeed neutral, isn't?

As far as evidence goes...hmmm

I am not sure what kind of evidence they're asking for, to be honest. Any hints?
 
Conservation of charge? Maybe if you assert that the universe was at one point, or at the beginning, neutral, it must always be?
 
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