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Tilting the Primordial Power Spectrum with Bulk Viscosity

James E. Lidsey
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Abstract

Within the context of the cold dark matter model, current observations suggest that inflationary models which generate a tilted primordial power spectrum with negligible gravitational waves provide the most promising mechanism for explaining large scale clustering. The general form of the inflationary potential which produces such a spectrum is a hyperbolic function and is interpreted physically as a bulk viscous stress contribution to the energy-momentum of a perfect baryotropic fluid. This is equivalent to expanding the equation of state as a truncated Taylor series. Particle physics models which lead to such a potential are discussed.

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James E. Lidsey. 1993-12-16. Tilting the Primordial Power Spectrum with Bulk Viscosity. https://doi.org/10.1093/mnras%2F266.2.489

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