🌐العربيةEnglishPolskiSvenskaTiếng ViệtРусскийالعربيةفارسی한국어日本語EntityQ5457948· pop 5استواءin cosmology, an absence of curvature of spaceAvailable in 5 languagesالعربيةBurmeseفارسی한국어via Wikidata sitelinks · CC0Connectionsflatness problemEntityCategoriesPhysical cosmology