A car company may boast that its latest and greatest model represents a "quantum leap" beyond anything else in its class. But while the manufacturer surely means to convince you that its newest sedan is a huge improvement over the competition, the word quantum means something entirely different to a physicist.
Scientifically speaking, a quantum is the smallest indivisible unit of energy [source: Rohrer]. Albert Einstein described photons as "quanta of light," meaning tiny, discrete particles, and in 1900, physicist Max Planck used the term quantum in his theory explaining the behavior of minute particles like photons and electrons at the subatomic level [sources: Quanta Magazine, Rohrer]. Suddenly that quantum leap doesn't seem like such a giant step forward. Indeed, a quantum leap would really be the tiniest change possible in an electron's energy level.
Of course, car commercials aren't the only place you'll hear the word quantum used questionably. One central principle of quantum mechanics is that material at the subatomic level can act as both a wave and a particle. But when an observer measures, for example, the exact position of a particle, the wave characteristics can no longer be observed [source: Swanson]. Self-help gurus like Deepak Chopra and Rhonda Byrne, the author of "The Secret," have oversimplified and misused this concept, incorrectly citing quantum physics as "proof" that observing something creates the thing -- therefore we can will the things we wish for into existence simply by visualizing them [source: Swanson].