I have a first-order RC circuit without source and capacitors initially charged to +5 V and -4 V as shown in the figure.
Initially charge sharing takes place between capacitors and v(a) = v(b) = 0.5 V. Then the voltage should get discharged through the resistor exponentially with a time constant of 2RC. But I am observing a linear discharge instantaneously (in ps). Why did this happen?
PS: zero-voltage source was included just to assign initial voltages across capacitors