Question:
Positronium is just like an H-atom with the proton replaced by the positively charged anti-particle of the electron (called the positron which is as massive as the electron). What would be the ground state energy of positronium?
Solution:
The lowest energy of the positronium is -6.8 electron volts
The highest energy level of the positronium which is the next to n = 1 that is n = 2 is -1.7 electron volt.