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Tilted spatially nonflat inflation

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Summary: In this study, analytical approximations for primordial power spectra with primordial spatial curvature are derived, showcasing effects such as cutoffs and oscillations at low multipoles. These effects are mathematically attributed to shifts in the wave vectors participating dynamically, offering insight into the generic predictions of primordial curvature independent of specific inflationary potentials.

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A Lasenby et al.

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G Chen et al.

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R Aurich et al.

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