Wave packet

A wave packet is a localized wavelike perturbation.

A 1D wave packet (with dispersion), propagating over time.

A snapshot of a 2D wave packet.

Wave-particle duality

In the context of quantum mechanics, particles can be thought of as wave-packets. That is, quantum particles are neither ideal point-like particles, nor ideal plane-waves. They are instead intermediate objects, which are certainly wave-like (e.g. can undergo interference), but also somewhat localized. The classical concepts of 'particle' (perfectly localized; mathematically a delta-function), and 'wave' (oscillation with a single well-defined wavelength, spread infinitely over all space) can be viewed as limited cases of the general wave-packet. These limiting cases are only conceptual: in reality neither can exist.

See Also

• Fourier transform
• Wikipedia: Wave packet