Is the Universe neutrally charged?

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cmb
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Summary:
Are there exactly as many negative charges as positive, in the universe?
Are there exactly as many negative charges as positive, in the universe?

If so, how can we be sure, and if not then what is the difference and why?

If there is an assumption of charge neutrality at time zero, then why? Is there a rationale behind that or just an unsupported supposition?
 

Answers and Replies

  • #2
anuttarasammyak
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If not neutral we have difficulty in counting lines of electric force which connects positive and negative charges. I do not say it is reason why but I am feeling uneasy about it.
 
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Drakkith
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If there is an assumption of charge neutrality at time zero, then why? Is there a rationale behind that or just an unsupported supposition?
Theories on the composition and evolution of the very, very early universe typically involve a transition from a higher energy state to a lower energy state. For example, inflation proposes that the very early universe contained an inflaton field, a field which contained a large amount of energy. After inflation this field decayed into the standard model particles and their corresponding fields. This decay process would likely have been governed by many different conservation laws, including charge conservation, ensuring a neutrally charged universe.
 
  • #4
cmb
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Theories on the composition and evolution of the very, very early universe typically involve a transition from a higher energy state to a lower energy state. For example, inflation proposes that the very early universe contained an inflaton field, a field which contained a large amount of energy. After inflation this field decayed into the standard model particles and their corresponding fields. This decay process would likely have been governed by many different conservation laws, including charge conservation, ensuring a neutrally charged universe.
OK, that is fine as an explanation, happy with that I was thinking that might be one of the possibilities.

So, basically, if we have 'energy' and, by whatever means, it is converted into matter, if any of that matter is made up of charged particles then it's ALWAYS as much charge of each polarity because the 'energy' was not charged thus the product mass cannot be charged, by conservation of charge?

And this is what we see in real high energy experiments? So if we wham, say, two protons together it cannot produce 'only' energy but all the products still have to tot up to two units of charge?

But does that mean a proton alone can never be 'entirely' converted to energy? If so, what does that mean in reaction to expressing its mass in MeV, if it cannot be all converted to energy?
 
  • #5
jbriggs444
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But does that mean a proton alone can never be 'entirely' converted to energy? If so, what does that mean in reaction to expressing its mass in MeV, if it cannot be all c
Energy is not a thing that you can convert to or from. https://www.feynmanlectures.caltech.edu/I_04.html Instead, it is a number that you can compute and can observe to be conserved.

You can convert between various things and observe that energy is conserved. In particular, if we had a pair of oppositely moving photons with enough combined energy, we could collide them (photon-photon interaction) and produce a proton plus anti-proton pair with the same total energy. Easier, if we had a proton and anti-proton pair, we could collide them and get a result with the same total energy.
 
  • #6
cmb
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Energy is not a thing that you can convert to or from.
Could you please help me understand that in the context of Drakkith's response?

..... inflation proposes that the very early universe contained an inflaton field, a field which contained a large amount of energy. After inflation this field decayed into the standard model particles and their corresponding fields.....
 
  • #7
jbriggs444
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Could you please help me understand that in the context of Drakkith's response?
There was a field. Then there were standard model particles. To the extent that energy conservation applies, the energy of both was the same.
 

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