Non-canonical kinetic structures in the swampland

Abstract

We consider how the swampland criteria might be applied to models in which scalar fields have nontrivial kinetic terms, particularly in the context of $P(\varphi ,X)$ theories, popularly used in approaches to inflation, to its alternatives, and to the problem of late-time cosmic acceleration. By embedding such theories in canonical multi-field models, from which the original theory emerges as a low-energy effective field theory, we derive swampland constraints, and study the circumstances under which these might be evaded while preserving cosmologically interesting phenomenology. We further demonstrate how these successes are tied to the phenomenon of turning in field space in the multi-field picture. We study both the general problem and specific examples of particular interest, such as DBI inflation.

16+3 pages. v2: added references

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Cited by in corpus (8)

• Multi-field dark energy: cosmic acceleration on a steep potential
• Reconstructing Quintessence
• Reconstructing k-essence: Unifying the attractor $n_S(N)$ and the swampland criteria
• A Well-Posed UV Completion for Simulating Scalar Galileons
• Swampland conjectures and single field inflation in non-standard cosmological scenarios
• Hitchhiker's Guide to the Swampland: The Cosmologist's Handbook to the string-theoretical Swampland Programme
• Generalizing the Swampland: Embedding $P(X,\phi )$ Inflationary Theories in a Curved Multi-field Space
• Positivity vs. Lorentz-violation: an explicit example