capacitor charging/discharging for R=0
the graph of i vs t will be the delta function
(delta func;f(x); is zero at all values except at 0, where it is infinitely large such that the integral of f(x) from -infinity to +infinity is equal to some finite value[here, CV])
physically what happens in this ideal situation is that all the requisite charge is transferred to the capacitor plates in infinitesimal time. therefore, i~q/t;t tends to 0, so i tends to infinity.