Why we are not allowed to connect ideal voltage sources in parallel

.when 2 elements are connected in a parallel connection the voltage across them must be same

when 2 voltage sources are connected they must have same potential difference across them which is not possible unless they are of same value and in the other case(different value sources) it is same as the greater valued voltage source since it overtakes the other one

Which means that there is no use in connecting both of them in parallel

hope this helps

It is either a  proton or a neutron im almost positive. hope this .