既然重力場中不存在能量與動量之密度,則應致力於 尋求各守恆量之準局域量.本文繼同一系列研究之後,探 討在廣義相對論理論中之質心距之準局域量,由此非但可 以再次驗証Nester-Chen expression之有效性,更能顯示 質心距較其他守恆量對各種表示式理論提供更嚴格之檢驗 標準 Having recognized the absence of energy and momentum density for the gravitational field, conserved quasilocal quantities over finite 3- dimensional regions are the best that can be expected. Nester-Chen expression for the quasilocal center-of-mass moment was investigated. Not only the result agrees with the expectated asymptotical limit value but also the center-of-mass moment behaves as a more strict criteria for the validity of the expression.