These results indicate that the future state of the second screen, as either present or not, has an effect on whether the photons leave the first screen as a particle or a wave. In essence, the future event (cause) would appear to dictate the past state (effect) of the helium atom, as if it somehow knew ahead of time whether the second screen was going to be inserted. This stands in stark contrast to how we perceive cause and effect in a linear conceptualization of time and indicates that our notion of time flowing only from past to future is largely a product of our perception. It also
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