I am wondering why it is the case the when resistors are connected in parallel the voltage drop over them must be the same?
The reason I have seen arguing for this is that the electrons before the resistors appears in the same place, and the electrons after the resistors appears at the same place. And that means that the electrons that goes through resistor \$R_1\$ and those going through resistor \$R_2\$ are at the state before and after.
But why does this argument hold? Voltage is energy per charge, why couldn't it be the case that even though the electrons are at the same place before and after going through the resistors, the work done on the electrons going through $R_1$\$R_1\$ is higher than the work done to the electrons going through resistor $R_2$\$R_2\$?