In other words, one could not ask what was really happening inside of an atom when nobody looked—according to Bohr, the quantum world could only be considered real in conjunction with some kind of measurement apparatus to study that world. And the behavior of the objects in that world, as indicated by such an apparatus, would be best described as either particles or waves, but never both simultaneously. These descriptions are contradictory—a particle has a definite location, which waves don’t; waves have frequencies and wavelengths, which particles don’t—yet Bohr claimed that this “inevitable
...more
