Abstract

The canonical multi-scalar field inflation where the kinetic and potential terms are sum-separable is ruled out by the current observations for the chaotic-type potential V=∑<inf>i</inf>μ<inf>i</inf>ϕ<inf>i</inf>^p. This paper explores the non-sum-separable case to validate the chaotic-type potential in the multi-scalar field, incorporating a linear coupling term between the kinetic and potential terms in the canonical Lagrangian. This coupling influences the slow-roll parameters and also alters our predictions for the spectral index n<inf>s</inf> and the tensor-to-scalar ratio r, which directly depend on those parameters. In fact, compared to standard canonical multi-field inflation, the values of n<inf>s</inf> and r decrease to levels consistent with the recent Planck+BICEP/Keck constraint.