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Dark Energy from Brane-world Gravity

Roy Maartens
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Abstract

Recent observations provide strong evidence that the universe is accelerating. This confronts theory with a severe challenge. Explanations of the acceleration within the framework of general relativity are plagued by difficulties. General relativistic models require a "dark energy" field with effectively negative pressure. An alternative to dark energy is that gravity itself may behave differently from general relativity on the largest scales, in such a way as to produce acceleration. The alternative approach of modified gravity also faces severe difficulties, but does provide a new angle on the problem. This review considers an example of modified gravity, provided by brane-world models that self-accelerate at late times.

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Roy Maartens. 2006-02-18. Dark Energy from Brane-world Gravity. https://doi.org/10.1088/1742-6596%2F68%2F1%2F012046%2010.1007%2F978-3-540-71013-4_11

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