{"paper":{"title":"Planck constraints on inflation in auxiliary vector modified $f(R)$ theories","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["gr-qc","hep-ph","hep-th"],"primary_cat":"astro-ph.CO","authors_text":"Mehmet Ozkan, Shinji Tsujikawa, Yi Pang","submitted_at":"2015-02-23T08:30:32Z","abstract_excerpt":"We show that the universal $\\alpha$-attractor models of inflation can be realized by including an auxiliary vector field $A_{\\mu}$ for the Starobinsky model with the Lagrangian $f(R)=R+R^2/(6M^2)$. If the same procedure is applied to general modified $f(R)$ theories in which the Ricci scalar $R$ is replaced by $R+A_{\\mu} A^{\\mu}+\\beta \\nabla_{\\mu}A^{\\mu}$ with constant $\\beta$, we obtain the Brans-Dicke theory with a scalar potential and the Brans-Dicke parameter $\\omega_{\\rm BD}=\\beta^2/4$. We also place observational constraints on inflationary models based on auxiliary vector modified $f(R)"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1502.06341","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}