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تسجيل مستخدم جديدEhlers symmetry at the next derivative order
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We analyse four-dimensional gravity in the presence of general curvature squared corrections and show that Ehlers SL(2,R) symmetry, which appears in the reduction of standard gravity to three dimensions, is preserved by the correction terms. The mechanism allowing this is a correction of the SL(2,R) transformation laws which resolves problems with the different scaling behaviour of various terms occurring in the reduction.
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