How often do we find ourselves using certain words, positively confident that we know what they mean, only to be flabbergasted to learn that they mean something else entirely? I remember when a friend asked me if I had “made an RSVP” for dinner yet, when she really should have asked me if I had made a “reservation” yet. What about the word quantum? Is that something that is really big or something that is really small?
In casual conversation, the most common place that you’ll find the word quantum being used is in the context of a quantum leap. We have come to understand a “quantum leap” as referring to a large and sudden change. The term was perhaps popularized by the TV show Quantum Leap and, in this context, “quantum” would refer to something big.
I’ve done this myself on multiple occasions, talking about how it took a quantum leap of faith to launch my freelance writing career, for instance. The problem is that the word quantum doesn’t actually refer to something large at all. In the context of science, it actually refers to something that is very small.
If we were to look up the definition of the word “quantum” in the dictionary, we’d learn that it is “the smallest amount of many forms of energy.” Not only is a quantum something small, in physics it is “the minimum amount of any physical entity involved in an interaction.” It’s as small as small can be.
Whether you’re talking about quantum theory, quantum physics or quantum mechanics, we’re talking about something on the smallest imaginable scale. There’s a great video explaining how quantum computers work if you want to understand why the technology will become increasingly important in the next few years.
In purely scientific terms, a quantum leap isn’t so much a large change as much as it is an abrupt change, oftentimes referring to the sudden movement an electron might make as it “leaps” from the orbit of one atom to another. It’s a “small” jump in terms of absolute distance. That is the “correct” meaning of the term, though we will all continue to use “quantum leap” informally to mean a big change spanning a figuratively large area.
English is a funny language, wouldn’t you say?
I can add to your point how communicating science requires a precise use of language. I had a awakening on how I needed to formally communicate to scientists when I saw someone get questioned on how something was “significantly” different. I learned very quickly that statistical calculations better be available to describe the significance level of that difference.