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In the circuit shown below, I am considering ground to be ideal earth ground (stays at 0V no matter how much current it absorbs). It is my understanding that current flows when there is a potential difference. Thus, I would expect current to flow to both the negative terminal of the battery and to ground. Why wouldn't current leak to ground? I am looking for a physics explanation.
The following two questions have addressed this issue (First, Second), but I am unsatisfied with the answers given. Specifically, one of the answers noted that the voltage source must have an equal out flow and in flow of current to sustainably generate an EMF. I don't see how this would affect whether or not current would leak to ground. Consider a source that doesn't have that constraint (it can infinitely output electrons with some set potential).