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How could they tell there were imaginary flashes? It seems like a private experiment, you can't check it. (Maybe there were not expected flashes at all and they

• mechanical_fish 18y ago
  Well, I left out the next sentence of the book, in which Geiger builds an electronic counter (perhaps you've heard of it? :) and uses it to cross-check the humans. According to the book, after using the counter to confirm that properly trained and rested humans were as accurate as the electronics, the next step was to put the electronic counter away because the humans could also give you spatial information: They could not only tell you that a flash had happened, but could tell you where it was in the visual field. Multichannel PMTs or (god bless 'em) chilled semiconductor-based multi-element low-noise photodetectors were still dozens of years in the future...
  • hhm 18y ago
    Thank you! Your posts are always very good reading :)
• deleted 18y ago
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• rflrob 18y ago
  There really is no good way to tell if there were imaginary flashes. Once you get down to really dim (i.e. low photon count) flashes, you're in the realm of Poisson statistics. So, on average, a flash of light might have 4 photons in it, but it could easily have 1 or 7. Or 0! http://en.wikipedia.org/wiki/Poisson_distribution http://en.wikipedia.org/wiki/Poisson_distribution