B How many electrons to make a stable gravitational object?

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Creating a stable gravitational object composed solely of electrons is fundamentally challenged by the significant electromagnetic repulsion between them, which is 23 orders of magnitude stronger than gravitational attraction. This repulsion prevents the formation of such an object under normal conditions, as electrons would naturally neutralize with positively charged particles. The discussion also briefly touches on neutrinos, which lack charge and could theoretically form a gravitational object, but their properties make crowding them together impractical. Ultimately, the consensus is that the charge-to-mass ratio of electrons ensures that gravitational attraction cannot overcome electromagnetic repulsion. Therefore, a stable object made entirely of electrons is not feasible.
Feynstein100
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I was wondering if we could have an object made up of only electrons. Normally, that wouldn't be possible because electrons repel each other. However, this repulsion can be overcome using gravity. So my question is, how many electrons would you need to have their gravitational attraction overcome the electromagnetic repulsion and form a stable object? Or perhaps is the charge-to-mass ratio of the electron such that the electromagnetic repulsion will always be higher than the gravitational attraction and thus preclude such an object?
Of course, an object like that would not form naturally since the electromagnetic force has the tendency to self-limit via neutralization. So for our purposes, we assume that there aren't any positively charged particles nearby to neutralize our object. There are only electrons.
 
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Feynstein100 said:
So my question is, how many electrons would you need to have their gravitational attraction overcome the electromagnetic repulsion and form a stable object?
What did you find when you did your Google searches to compare the electrostatic force to the gravitational force at typical atomic lattice distances?
 
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berkeman said:
What did you find when you did your Google searches to compare the electrostatic force to the gravitational force at typical atomic lattice distances?
That the electromagnetic force is 23 orders of magnitude stronger than gravity.
Feynstein100 said:
Or perhaps is the charge-to-mass ratio of the electron such that the electromagnetic repulsion will always be higher than the gravitational attraction and thus preclude such an object?
So I guess this is the answer?
 
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Feynstein100 said:
That the electromagnetic force is 23 orders of magnitude stronger than gravity.
Boom! :wink:
 
berkeman said:
Boom! :wink:
I'll take that as a yes 😂 But not so fast. We've still got neutrinos. They don't have charge. So I know you can make a gravitational object out of them 😃 So, indulge me. How many would it take?
 
Neutrinos don't like crowds, so that would not work. They also hate to be anthropomorphized, so I'll have to tie off this thread now before they get their neutrino union involved... :wink:
 
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