Equations · equation

De Broglie Wavelength

Quantum · 1924

Equation: λ = h/p
Field: Quantum
Named After: Louis de Broglie
Symbols: λ wavelength associated with a particle · h Planck constant · p momentum
Year: 1924

Significance

If light can act like particles, matter can act like waves — every moving thing has a wavelength. Electrons diffract like light does, which is why electron microscopes see atoms and why atoms have discrete orbitals at all.

Theories

Quantum Mechanics Wave–Particle Duality

Related

Bragg's Law Planck–Einstein Relation Bloch's Theorem Bohr Model Energy Levels

Constants

Electron mass Planck constant

Requires

Momentum and Impulse Wave Speed

Elements

Referenced by

constant

Electron mass Planck constant

element

equation

Bloch's Theorem Bohr Model Energy Levels Bragg's Law Momentum and Impulse Planck–Einstein Relation Wave Speed

theory

Quantum Mechanics Wave–Particle Duality

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From the Equations database in Notion, last edited 2026-08-18. This page is the row, rendered by the build; nothing on it is written by hand.