🌐EnglishEnglishDeutschEspañolPortuguêsSvenskaРусский中文日本語EntityQ233699· pop 11· linked from 19 articlesSecond soundquantum mechanical phenomenon in which heat transfer occurs by wave-like motionAvailable in 11 languagesEspañolDeutsch日本語РусскийPortuguêsCatalanCzechMalaySvenskaUkrainianvia Wikidata sitelinks · CC0ConnectionscopperEntityheliumEntityCategoriesLev LandauQuantum mechanicsSuperfluidityThermodynamics