Determine the full Kaluza–Klein spectrum in general flux compactifications

Determine the full Kaluza–Klein spectrum for general flux compactifications in order to establish when massive modes can be integrated out to obtain a finite-dimensional effective theory.

Background

The paper constructs an off-shell real superpotential while retaining the full tower of Kaluza–Klein modes, because a finite-dimensional truncation is generally unavailable. Determining the complete Kaluza–Klein spectrum would clarify which modes constitute a valid light sector and whether a conventional lower-dimensional effective supergravity can be derived.

References

For a general flux compactification, it is not known how to determine the full Kaluza--Klein spectrum, and so usually one cannot integrate out the massive modes to obtain a conventional effective theory with finitely many fields.

— A real superpotential for M-theory on eight-manifolds  (2610.12439 - Ashmore et al., 8 Oct 2026) in Section 1, Introduction

Moreover, since backgrounds with and without fluxes often have drastically different geometric and even topological properties, it is often unclear whether the effective theory derived from the fluxless compactification is trustworthy after turning on fluxes.

— A real superpotential for M-theory on eight-manifolds  (2610.12439 - Ashmore et al., 8 Oct 2026) in Section 1, Introduction