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We calculate the bubble nucleation rate in a fourth-order gravity theory whose action contains an R term, under the thin-wall approximation, by two different methods. First the bounce solution is found for the Euclidean version of the original action. Next, we use a conformal transformation to transform the theory into general relativity with an additional scalar field and then proceed to find ...
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The field equations following from a Lagrangian L(R) will be deduced and solved for special cases. If L is a non-linear function of the curvature scalar, then these equations are of fourth order in the metric. In the introduction we present the history of these equations beginning with the paper of H. Weyl from 1918, who first discussed them as alternative to Einstein’s theory. In the third par...
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S. Deser* Physics Department, Brandeis University, Waltham Massachusetts 02454, USA and Lauritsen Laboratory, California Institute of Technology, Pasadena California 91125, USA (Received 28 April 2009; published 2 September 2009) Canonical analysis of a recently proposed linearþ quadratic curvature gravity model in D 1⁄4 3 establishes its pure, irreducibly fourth derivative, quadratic curvature...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2011
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.84.084022