Why Quantum Mechanics?#

What you need to know

  • Quantum mechanics is the fundamental theory of nature, governing atoms, molecules, and subatomic particles.

  • Quantum theories (quantum mechanics + quantum field theory) are complete descriptions of physical reality. And they’ve never failed an experimental test since their discovery!

  • Predictions of quantum mechanics have been verified to an astonishing degree of accuracy.

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Fig. 1 Quantum mechanics provides the framework to understand, describe, and predict the behavior of the smallest particles—so long as they don’t travel near light speed.#

Beware: Quantum Mechanics is Weird 🤯#

  • Saying QM is “weird” is an understatement. Don’t just take my word for it—consider Richard Feynman:

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Fig. 2 Richard Feynman, Nobel Prize in Physics (1965) for his groundbreaking work on quantum electrodynamics.#

“I think I can safely say that nobody understands quantum mechanics.” — Richard Feynman

  • Be prepared to let go of the comforting notion that “things make sense.” In quantum land, they often don’t! But that doesn’t stop us from mastering the logic of quantum mechanics and applying it everywhere—from chemistry to computing.

Bottom line: if you feel you don’t fully understand QM, don’t worry—you’re in good company… with everyone else!

How Does Quantum Mechanics Compare to Other Theories?#

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Fig. 3 “There are no quantum mechanicians. Electrons don’t break down, but your car does!”#

Even though discovered by physicists, QM isn’t just “another” physical theory like electromagnetism or relativity.

In the usual hierarchy of sciences (biology → chemistry → physics → math), quantum mechanics sits in a unique position—like the operating system on which other theories run as “apps.” Translating a theory into this OS is what physicists call quantization.

Scott Aaronson, Quantum Computing Since Democritus (2013)

Where is Quantum Mechanics Applied?#

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Fig. 4 Applications in Quantum Chemistry#

  • Chemical bonds, molecular structure, reactivity, color, material properties

  • Spectroscopy (NMR, UV–Vis, IR, lasers…)

  • Modern electronic structure calculations

  • Condensed matter physics

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Fig. 5 Applications in Quantum Computing#

  • Quantum algorithms and simulation

  • Cryptography and security

  • Materials and drug discovery

What Skills Will You Gain?#

Studying quantum mechanics will arm you with tools beyond physics:

  • Probabilistic thinking and comfort with uncertainty

  • Linear algebra + differential equations at a deeper, applied level

  • Ability to decode electronic structure calculations in cutting-edge research (chemistry, biochemistry, materials, astrophysics)

  • Insight into chemical bonding, spectroscopy, and reactivity

  • A more nuanced appreciation of the complex world we live in

And One More Thing…#

If none of the above convinces you, remember: studying quantum mechanics also upgrades your meme game.

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Fig. 6 Have a quantum joke ready for any occasion.#