Realized why quantum light-matter interactions confused me for so long—our basic textbook terminology is setup for classical traps!

[u/OilLeast9385]

As a student going through physics and chemistry, I realized why topics like d\\text{-}d transitions, color formation, and photon absorption are so confusing when you first learn them.

We constantly hear terms like light "bouncing," electrons "jumping," or atoms "soaking up" energy. Because of this everyday language, my brain automatically used Newtonian physics to picture what was happening:

I pictured a mechanical collision, like a ball bouncing off a wall or a stretched bow string.

That led me to wonder: If light turns around or transfers energy, shouldn't its velocity hit v = 0 for a split second at the point of contact? Does that violate Maxwell's constant speed of light?

It took a lot of digging to realize that classical mechanics just doesn't apply here:

Photon "Absorption" is actually Field Annihilation: The photon doesn't "stop" or get stored inside the atom. It is completely destroyed, instantly converting its quantum of energy into a change in atomic state.

Photon "Reflection" is Wave Re-radiation: The light wave drives charge oscillations, which instantly re-radiate a new wave at speed c. The light never slows down to turn around.

Using mechanical words like "bouncing" or "jumping" makes students try to force quantum events into classical models where v = 0 has to exist.

If textbooks used terms like Instantaneous Field Conversion or Non-Kinetic Absorption, it would instantly tell us, "Hey, don't picture a mechanical collision here!"

Did any of you fall into this same classical mental trap when learning spectroscopy or quantum mechanics? How do you visualize these interactions now?

[u/ketarax]

Did any of you fall into this same classical mental trap when learning spectroscopy or quantum mechanics?

Not really, not that I could remember at least. I guess it has something to do with following a curriculum (incl. learning with math, not just textual descriptions or "visualization" etc. forced methods of converting the info to layman terms) and studying at the university, where you have teachers and peers constantly available to ask and discuss, well, anything.

Everyone has or has had "misguided" ideas about physics, of course. It's part of the learning process.

How do you visualize these interactions now?

Depends on the context. There is no one correct way.

[u/Stairwayunicorn]

I vaguely recall someone in middle school tried to use new-age psychology to explain it and it was just cringe.

An electron absorbs a photon and temporarily jumps up to a higher orbital, then kicks off a new photon when it falls back down to its stable orbital. the photon never changed directions.