# Multi-field Inflation in High-Slope Potentials

## TL;DR

This paper introduces two multi-field inflation models compatible with Planck data that satisfy swampland conjectures, featuring high turning rates and curved field-space metrics, with distinct predictions for tensor-to-scalar ratios.

## Contribution

It presents novel multi-field inflation models with specific geometric and dynamical properties that align with swampland criteria and observational constraints.

## Key findings

- Helix-type potential yields a tensor-to-scalar ratio just below current limits.
- Orbital inflation model achieves prolonged inflation with exponential perturbation growth.
- Both models identify parameter regions compatible with Planck data and nucleosynthesis constraints.

## Abstract

We present two families of multi-field potentials that support inflation while satisfying the refined de Sitter and the distance swampland conjectures. Both families feature Planck-compatible phenomenology. The first is a helix-type potential, in a flat field-space metric, that satisfies the conjectures via a high turning rate. This model has a tensor-toscalar ratio close to, but below, the current experimental limits and small non-gaussianities. The second family, an example of orbital inflation, utilizes a negatively curved field metric to achieve prolonged inflation with nontrivial turning in the presence of a tachyonic direction. Although perturbations in this model undergo an exponential growth before horizon exit, it is always possible to match the measured amplitude of the power spectrum by lowering the scale of inflation if the turning rate is low enough. We identify a Planck-compatible region of parameter space in which the scale of inflation is above that of nucleosynthesis. Due to the rapid growth, this model predicts an exponentially suppressed value for the tensor-to-scalar ratio.