Niobium capacitor
The development of solid electrolyte tantalum capacitors began in the early 1950s as a miniaturized, more reliable low-voltage support capacitor to complement the newly invented transistor. The solution found by R. L. Taylor and H. E. Haring of the Bell Labs was based on experience with ceramics. They ground down tantalum to a powder, pressed this powder into a cylindrical form and then sintered the powder particles into a pellet (“slug”) at high temperatures, between 1500 and 2000 °C, under vacuum conditions. These first sintered tantalum capacitors used a non-solid electrolyte not consistent with the concept of solid state electronics. 1952 a targeted search in the Bell Labs for a solid electrolyte by D. A. McLean and F. S. Power led to the invention of manganese dioxide as a solid electrolyte for a sintered tantalum capacitor.
Two capacitor paradox
The two capacitor paradox or capacitor paradox is a paradox, or counterintuitive thought experiment, in electric circuit theory. The thought experiment is usually described as follows: 
Two identical capacitors are connected in parallel with an open switch between them. One of the capacitors is charged with a voltage of formula_1, the other is uncharged. When the switch is closed, some of the charge formula_2 on the first capacitor flows into the second, reducing the voltage on the first and increasing the voltage on the second. When a steady state is reached and the current goes to zero, the voltage on the two capacitors must be equal since they are connected together. Since they both have the same capacitance formula_3 the charge will be divided equally between the capacitors so each capacitor will have a charge of formula_4 and a voltage of formula_5. At the beginning of the experiment the total initial energy formula_6 in the circuit is the energy stored in the charged capacitor: 
At the end of the experiment the final energy formula_8 is equal to the sum of the energy in the two capacitors 
Thus the final energy formula_8 is equal to half of the initial energy formula_6. Where did the other half of the initial energy go?