Convert Electron Radius (re) to Ken (ken) instantly.
About these units
Electron Radius (re)
The classical electron radius, approximately 2.818 × 10⁻¹⁵ meters, is a theoretical value derived from classical electromagnetic theory rather than an actual measured size. It represents the radius a charged sphere would need to have in order for its electrostatic self-energy to equal the electron's rest energy. Although electrons are now understood to be point-like or extremely small compared to this radius, the classical electron radius remains useful in scattering theory, especially in calculations involving Thomson scattering — the elastic scattering of electromagnetic radiation by free electrons. Thus, while not a physical dimension of the electron, the classical radius serves as a meaningful parameter in specific areas of physics and retains importance in radiation modeling and plasma physics.
Ken (ken)
The ken is a traditional Japanese unit of length, typically about 1.8 meters, though historically it ranged from 1.6 to 1.9 meters depending on the era and region. The ken is deeply tied to traditional Japanese architecture, especially temple and shrine construction. In classic building design, the ken measured the spacing between pillars in wooden structures. Because Japanese architecture emphasizes modularity and harmonious proportions, the ken allowed builders to create spaces that were both structurally efficient and aesthetically consistent. Many tatami room layouts are also derived from ken-based proportions. Beyond architecture, the ken carried symbolic importance in religious and cultural contexts. Temples were often laid out using ken multiples, reinforcing a sense of order, symmetry, and sacred geometry. Even though modern Japan uses the metric system, the ken persists in the restoration and preservation of historical buildings.