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arXiv · 0911.5343

Inflation on the Brane with Vanishing Gravity

Jason Gallicchio·Rakhi Mahbubani
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Abstract

Many existing models of brane inflation suffer from a steep irreducible gravitational potential between the branes that causes inflation to end too early. Inspired by the fact that point masses in 2+1 D exert no gravitational force, we propose a novel unwarped and non-supersymmetric setup for inflation, consisting of 3-branes in two extra dimensions compactified on a sphere. The size of the sphere is stabilized by a combination of a bulk cosmological constant and a magnetic flux. Computing the 4D effective potential between probe branes in this background, we find a non-zero contribution only from exchange of level-1 KK modes of the graviton and radion. Identifying antipodal points on the 2-sphere projects out these modes, eliminating entirely the troublesome gravitational contribution to the inflationary potential.

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Jason Gallicchio, Rakhi Mahbubani. 2009-11-30. Inflation on the Brane with Vanishing Gravity. https://doi.org/10.1007/jhep04(2010)068

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