Array ( [0] => Array ( [title] => L57A [link] => https://www.youtube.com/embed/WFFTcc_w6jE ) ) 國立清華大學開放式課程OpenCourseWare(NTHU, OCW) - 第57講|Lecture 12 Electrodynamics and Relativity|12_1A 12_1 The Special Theory of Relativity