So to explain that -- if you've got an elementary particle and you shine a light on it, then the photon of light has momentum, which knocks the particle, so you don't know where it was before you looked at it.
Da objasnim -- ako imate osnovnu česticu i obasjate je svjetlošću, onda foton svjetlosti ima impuls, koji udara o česticu, tako da ne znate gdje je bila prije nego što ste je ugledali.