Quantum Duality: 18 flashcards

The concept in quantum mechanics that every quantum entity (like light or electrons) exhibits both wave and particle properties, depending on the experiment.

The double-slit experiment, where light passing through two slits creates an interference pattern of bright and dark bands, characteristic of waves.

The photoelectric effect, where light hitting a metal surface ejects electrons, and the energy of the ejected electrons depends on the frequency (color) of light, not its intensity.

A quantum particle of light that carries a discrete amount of energy, given by E = hf, where h is Planck's constant and f is the frequency.

The wavelength associated with a moving particle, given by λ = h/p, where h is Planck's constant and p is the momentum.

Each electron lands as a single dot (particle behavior), but over time, the dots accumulate to form an interference pattern (wave behavior).

The emission of electrons from a metal surface when light of sufficient frequency shines on it. The effect cannot be explained by classical wave theory.

The minimum energy required to eject an electron from a metal surface. The kinetic energy of the ejected electron is given by KE = hf - φ.

A fundamental constant that relates the energy of a photon to its frequency. Its value is approximately 6.626 × 10⁻³⁴ J·s.

It demonstrates the wave nature of light and matter, and shows that the act of measurement (observing which slit a particle goes through) destroys the interference pattern.

The increase in wavelength (decrease in energy) of X-rays when they scatter off electrons, demonstrating that photons carry momentum and behave like particles.

A mathematical function that describes the quantum state of a particle. Its square (|ψ|²) gives the probability of finding the particle at a given position.

It is impossible to simultaneously know both the exact position and exact momentum of a particle. The product of the uncertainties is at least h/(4π).

A classical particle has a definite position and momentum at all times, while a quantum particle is described by a wave function and exhibits wave-like behavior until measured.

Electron microscopy, where the wave nature of electrons (with much smaller wavelength than light) allows imaging at atomic resolution.

That light and matter have both wave and particle properties, and which property is observed depends on the experiment performed.

The maximum kinetic energy of ejected electrons depends on the frequency of light, not its intensity, and there is a cutoff frequency below which no electrons are emitted.

That all matter has wave-like properties, with a wavelength given by λ = h/p. This was later confirmed by electron diffraction experiments.