i was watching the Brian Cox 'night with the stars'. He said that no 2 electrons can have the same energy state. Is this correct? i thought they couldn't have the same quantum numbers but can even share the same orbital (thus same energy). I also thought this applied to the same atom only, but he stated it applies to the universe and every time an electron in an atom jumps to a new energy state, actually he just said has more energy, then every electron in the universe has to adjust its energy state, instantly. Can someone put some detail on this as i havent come across this before. The only understanding i have of particles seemingly being able to communicate instantly no matter how far apart they are is in entanglement, but he didnt seem to be suggesting this was the mechanism.