Punktliknande

Punktliknande (Swedish: “point‑like”) is a descriptive term used primarily in science and astronomy to denote objects, phenomena, or distributions that approximate a single point in space. The adjective emphasizes that an object’s spatial extent is negligible compared to the observational scale, so it behaves as though all its mass, charge, or light originates from a single location.

In classical physics, the point‐charge model treats electric charges as pointlike, enabling simplified calculations of electric fields while neglecting finite size effects. Similarly, in fluid dynamics, point vortices are idealisations of concentrated rotational motion. In particle physics, fundamental particles such as electrons, quarks, and neutrinos are described as pointlike, a concept tested through high‑energy scattering experiments that reveal no substructure down to distances of 10^−18 m (ATLAS and CMS, 2020).

Astronomical applications of punktliknande are widespread. A point source refers to an astronomical object whose angular size is smaller than the telescope’s resolution, such as many distant quasars or supernovae. Point‐like X‑ray emission can indicate accretion discs around compact objects. The term is also applied to the Sun’s corona during solar flares, where localized, almost instantaneous brightenings appear.

In broader contexts, punktliknande is used metaphorically in literature and the arts to describe brief, intense moments that dominate perception. The term remains a standard descriptor in Swedish scientific literature and general usage when precision about spatial extension is required.

See also: Punkt, point source, point charge.

References: ATLAS Collaboration, “Search for substructure in high‑mass top‑like resonances,” JHEP, 2020; National Astronomical Observatory, “Star Catalog: Point‑like sources,” 2019.