不確定性

• Reading: ふかくていせい
• Romaji: fukakuteisei
• Kanji breakdown: 不 (fu) — not, un-; 確 (kaku) — certain, definite; 定 (tei) — fix, determine; 性 (sei) — nature, quality
• Pronunciation: /ɸɯ.ka.kɯ.teː.seː/

Meaning

Uncertainty; indeterminacy. The quality of being fundamentally unpredictable or imprecisely defined, especially as formalised in quantum mechanics.

Most famously associated with Heisenberg's Uncertainty Principle (不確定性原理), this term refers to the fundamental limit on the precision with which certain pairs of physical properties can be simultaneously known. More broadly used in statistics, economics, and decision theory to denote measurement limitations or inherent variability.

Examples

1. 量子力学における不確定性は、観測の技術的限界とは本質的に異なる。 Uncertainty in quantum mechanics is fundamentally different from the technical limitations of observation.
2. 不確定性原理によれば、粒子の位置と運動量を同時に正確に測定することはできない。 According to the uncertainty principle, it is impossible to simultaneously measure both the position and momentum of a particle with precision.
3. 市場の不確定性に対応するため、企業はリスク管理体制を強化した。 To cope with market uncertainty, the company strengthened its risk management framework.

Usage Guide

Context: quantum physics, statistics, economics, science

Tone: analytical

Origin & History

Compound of 不 (negation) + 確定 (definite, certain) + 性 (quality). Popularised in scientific Japanese through translations of Heisenberg's work in the early twentieth century.

Cultural Context

Era: Showa–Modern

Generation: Adults (academic)

Social background: Academic/Scientific