In 1924, Louis De Broglie proposed [[Wave-particle duality]], the idea that matter ([[proton]]s and [[electron]]s for example) had a wave-like nature.<ref>http://www.nobelprize.org/nobel_prizes/physics/laureates/1929/broglie-bio.html</ref> Here too, is Planck's constant:
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In 1924, Louis De Broglie proposed [[Wave-particle duality]], the idea that matter ([[proton]]s and [[electron]]s for example) had a wave-like nature.<ref>https://www.nobelprize.org/nobel_prizes/physics/laureates/1929/broglie-bio.html</ref> Here too, is Planck's constant: