I have asked this question in this forum twice before and received no meaningful answer. So I thought I would give it one last try and perhaps explain the question in a little more detail to explain what information I am looking for. I honestly did not think I would have to use any significant detail in a forum of physicists, but then I thought that maybe people in the forum don’t really understand what I’m getting at: hence, more detail in the question. If I receive another completely inadequate answer I’ll have to conclude that all the physicists who read this forum do not understand what they know and move on to another physics forum, maybe a more international one. So, here’s the question again: Regarding the emission and absorption frequencies of the hydrogen atom. I’ve read that the emission and absorption frequencies are the same for a jump (up or down) from the same quantum levels. While the emissive frequencies are obvious, the absorption frequencies are not. My question is; how is it known that the absorption frequencies are the same as the emissive frequencies? Given the experiments that are done to stimulate the hydrogen atoms to make these quantum jumps, I would assume that when the atoms absorb photons, they are absorbing them from a source. What is the source? If the source is ambient light then this could be easily verified by simply conducting the experiment in a dark room with absolutely no light. If the experiment continues to emit light then the conclusions regarding absorption are incorrect and there are a couple of possible explanations. The first would be that the applied voltage used to stimulate the hydrogen atoms are part of the equation. In other words the voltage is causing the up jump. Another possibility is that the experiment is ‘feeding on itself’. That is, it is taking something from the surrounding hydrogen atoms in order to make the jump. This could be verified by weighing the test sample before and after to see if anything is lost. (This should have been done anyway.) If it is feeding on itself then it would eventually wind down. If absorption does take place from ambient light then, in a completely dark room, there should be no emissions at all. (Don’t stumble over the furniture.) Once verified that the absorption process needs ambient light, the frequencies could be verified by emitting monochromatic frequencies (in the dark room) at the emissive frequencies to sustain (or start) the emissions. If the conventional emissive frequencies (410nm, 434nm, 486nm, or 656nm (or the newer infrared)) do not start the ball rolling then other monochromatic frequencies can be used until the actual absorption frequencies are discovered. Since Balmer's math was written to explain the experiments, it is not a reliable source of evidence, as well Lyman's or Paschen's or Bohr's math. You can email me at firstname.lastname@example.org if you don’t want to use this forum, especially if you think that I have been so stupid that you prefer not to embarrass me publicly. I am good at stupid, sometimes.