A curious observer’s guide to quantum mechanics, pt. 3: Rose colored glasses 

One of the quietest revolutions of our current century has been the entry of quantum mechanics into our everyday technology. It used to be that quantum effects were confined to physics laboratories and delicate experiments. But modern technology increasingly relies on quantum mechanics for its basic operation, and the importance of quantum effects will only grow in the decades to come. As such, physicist Miguel F. Morales has taken on the herculean task of explaining quantum mechanics to the rest of us laymen in this seven-part series (no math, we promise). Below is the third story in the series, but you can always find the starting story here.

So far, we’ve seen particles move as waves and learned that a single particle can take multiple, widely separated paths. There are a number of questions that naturally arises from this behavior—one of them being, “How big is a particle?” The answer is remarkably subtle, and over the next two weeks (and articles) we’ll explore different aspects of this question.

Today, we’ll start with a seemingly simple question: “How long is a particle?”