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摘要
En 中文
A study is made of the possible holonomy group types of a spacetime for which the energy-momentum tensor corresponds to a null or non-null electromagnetic field, a perfect fluid or a massive scaler field. The case of an Einstein space is also included. The techniques developed are, in addition, applied to vacuum and conformally flat spacetimes and contrasted with already known results in these two cases. Examples are given.
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