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Wave-particle duality - a discursive

Raymond Zheng

3 min read

Oct 30, 2023



Science is often filled with what is at best, jargon, or at worse, misnomers. In module 8 Physics, we conclude our foray into atomic models with the De Broglie and Schrodinger models. Central to these is the idea that quantum objects appear to behave as both waves and particles. Hence, we say they exhibit "wave-particle duality". In class, we discussed the sheer ridiculousness of this by likening it to cylinders with “square-circle duality”.

One of our top physics students, Raymond Zheng from North Sydney Boys, was inspired by this for his Module C English discursive – for which he scored full marks!

Wave-particle duality

I. The wavefunction

Essay commissioned by the University of Vienna, 1930

Consider this funky object. When observed in one experiment, it looks like a square, but in another, looks like a circle.

As a quantum physicist, I might say that the object exhibits some sort of square-circle duality. But you might as well just say it's a cylinder, only viewed from different perspectives.

Quantum mechanics is inherently underpinned by this exact paradox, that everything in nature can exhibit both wave and particle properties.

I still remember reading Schrodinger’s paper for the first time - the bristles of wheatgrass tickling my back whilst the pages glistened under the dwindling daylight. A bluebird perched itself on one thin arm of a birch tree, preening its gossamer wings with sporadic jabs of its beak.

Schrodinger writes that when you aren’t observing, matter moves as waves, where the probabilities of their position follows a wavefunction.

I closed my eyes, allowing my mind to sink into the darkness as I became untethered from the material world. I saw a wave, a manic disruption amidst a silent black background. It was the wavefunction of the bluebird, oscillating back and forth. How beautiful it was, nature and its secrets, fueled by the power of Schrodinger's words.

And he predicts that when I open my eyes to observe the wavefunction, it collapses into particles. Predicts, but doesn’t explain.

Recall the funky object I introduced to you, which you so presumptuously deemed to be a cylinder. Schrodinger never attempts to explain what exactly the wavefunction is, and thus his wave-particle duality tells us that our intuition of the universe is missing the full picture; it’s missing the cylinder. Sometimes, it pains me that I can’t explain why the bluebird warbles in unknown yearning.

II. Observing the wavefunction

An article for The Daily Express, 1965

My father was killed by the atomic bomb.

All I have left of him is a book he’d given me, Schrodinger’s “Science and Humanism”. Yes, that Schrodinger, the father of quantum mechanics, which governs the subatomic realm and all things nuclear; the scientist who killed Father.

He writes,

“Science cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight.”

The ineffable force of Father’s death was pure suffering. Often still, it’s too much. And to that, what does science say? The pain spears beyond the material world that science constructs for us.

“Science cannot tell us a word about why music delights us, of why and how an old song can move us to tears.”

Father would bring us into the woods, where the leaves, kissed with a familiar zephyr, sighed in subliminal tandem. A bluebird would hum a melody, its song that of the reverberant glory of life. But it sings not only of euphoric beauty and merriment, but of fleeting tragedies, of torment and woe. As I have come to accept, pain is everywhere in nature. That’s the beauty of it; it understands that familiar chasm of sheer anguish.

Perhaps then, Schrodinger and I are not so unlike. Perhaps it wasn’t his science that killed Father, but rather those who wielded its power.

Then with a beating of its wings, the bluebird lifts off to the firmament above. 

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