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arXiv · 1004.1417

Brane Annihilations during Inflation

Diana Battefeld·Thorsten Battefeld·Hassan Firouzjahi·Nima Khosravi
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Abstract

We investigate brane inflation driven by two stacks of mobile branes in a throat. The stack closest to the bottom of the throat annihilates first with antibranes, resulting in particle production and a change of the equation of state parameter w. We calculate analytically some observable signatures of the collision; related decays are common in multi-field inflation, providing the motivation for this case study. The discontinuity in w enters the matching conditions relating perturbations in the remaining degree of freedom before and after the collision, affecting the power-spectrum of curvature perturbations. We find an oscillatory modulation of the power-spectrum for scales within the horizon at the time of the collision, and a slightly redder spectrum on super-horizon scales. We comment on implications for staggered inflation.

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Diana Battefeld, Thorsten Battefeld, Hassan Firouzjahi, Nima Khosravi. 2010-04-08. Brane Annihilations during Inflation. https://doi.org/10.1088/1475-7516/2010/07/009

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