{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:19:46Z","timestamp":1760242786980,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2016,6,28]],"date-time":"2016-06-28T00:00:00Z","timestamp":1467072000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In this paper, we investigated inflationary solutions for a subclass of Horndeski models where a scalar field is non-minimally coupled with the Gauss\u2013Bonnet invariant. Examples of canonical scalar field and k-essence to support the early-time acceleration are considered. The formalism to calculate the perturbations in a Friedmann\u2013Robertson\u2013Walker (FRW) universe and to derive the spectral index and the tensor-to-scalar ratio is furnished.<\/jats:p>","DOI":"10.3390\/sym8070057","type":"journal-article","created":{"date-parts":[[2016,6,29]],"date-time":"2016-06-29T06:20:33Z","timestamp":1467181233000},"page":"57","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["k-Essence Non-Minimally Coupled with Gauss\u2013Bonnet Invariant for Inflation"],"prefix":"10.3390","volume":"8","author":[{"given":"Ratbay","family":"Myrzakulov","sequence":"first","affiliation":[{"name":"Department of General &amp; Theoretical Physics and Eurasian Center for Theoretical Physics, Eurasian National University, Astana 010008, Kazakhstan"}]},{"given":"Lorenzo","family":"Sebastiani","sequence":"additional","affiliation":[{"name":"Department of General &amp; Theoretical Physics and Eurasian Center for Theoretical Physics, Eurasian National University, Astana 010008, Kazakhstan"}]}],"member":"1968","published-online":{"date-parts":[[2016,6,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Linde, A.D. 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