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arXiv · 1703.09663

Non-minimal derivative coupling in Palatini cosmology: acceleration in chaotic inflation potential

Somphoach Saichaemchan·Burin Gumjudpai
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Abstract

NMDC-Palatini cosmology in slow-roll regime is of our interests. We present flat FLRW cosmological NMDC-Palatini field equations and acceleration condition. Late time trajectory is approximated. Chaotic inflation potential is considered here as it is viable in a range of positive coupling constant as constrained by CMB results. Phase portraits show that the NMDC-Palatini gives new saddle-point solutions. In $V \propto ϕ^2$ potential, the NMDC-Palatini effect enlarges the acceleration-allowed region from that of GR case.

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Somphoach Saichaemchan, Burin Gumjudpai. 2017-08-21. Non-minimal derivative coupling in Palatini cosmology: acceleration in chaotic inflation potential. https://doi.org/10.1088/1742-6596%2F901%2F1%2F012010

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