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arXiv · 2506.18456

Observational constraints on inflationary models with non-minimally derivative coupling by ACT

Qing Gao·Yanjiang Qian·Yungui Gong·Zhu Yi
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Abstract

The most recent data release from the Atacama Cosmology Telescope (ACT) reveals a larger value of the scalar spectral tilt $n_s$, ruling out a broad class of inflationary attractors. In this paper, we consider inflationary models including the power law potential, the hilltop model, the polynomial $\alpha$-attractor and exponential $\alpha-$attractor, with non-minimally derivative coupling in the high friction limit, and show how the models can fit ACT data. We also derive constraints on the model parameters using the latest ACT data.

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Qing Gao, Yanjiang Qian, Yungui Gong, Zhu Yi. 2025-06-23. Observational constraints on inflationary models with non-minimally derivative coupling by ACT. https://doi.org/10.1088/1475-7516%2F2025%2F08%2F083

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