the.com/curvature
How much a thing refuses to be a straight line, measured precisely.
means A measure of how sharply something bends or deviates from flatness at a given point.
from From Latin curvatura, built from curvus 'bent, crooked,' plus the noun-forming suffix -tura. Curvus itself traces back to a Proto-Indo-European root meaning to bend or turn — the same deep root that gives English words like crook, crank, and circle their twist. The word entered English in the 1600s through geometry and mechanics, where mathematicians needed a precise term for 'degree of bending' rather than just 'bentness' in general.
- zero case
- straight lines and flat planes have none
- einstein's trick
- gravity is just curved spacetime, not a force
- sphere math
- smaller sphere means tighter curvature, always
- sign matters
- saddle shapes curve negatively, spheres positively