ar X iv : a st ro - p h / 06 10 73 4 v 2 10 N ov 2 00 6 Matter instability in modified gravity
نویسنده
چکیده
The Dolgov-Kawasaki instability discovered in the matter sector of the modified gravity scenario incorporating a −μ/R correction to Einstein gravity is studied in general f(R) theories. A stability condition is found in the metric version of these theories to help ruling out models that are unviable from the theoretical point of view. For example, the theories f(R) = R + αμ/R, where α and n are real constants and n > 0, are ruled out for any negative value of α.
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