【摘 要】
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By studying the G(o)del-type solution,the causality in f(R)gravity with an arbitrary coupling between matter and geometry is discussed.Assuming that the matter
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By studying the G(o)del-type solution,the causality in f(R)gravity with an arbitrary coupling between matter and geometry is discussed.Assuming that the matter source is a perfect fluid and a scalar field,respectively,we find that for the perfect fluid case,noncausal G(o)del-type solutions exist and there is a critical radius rc beyond which the causality is violated.For the scalar field case,the violation of causality is forbidden.
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