Emergence in String Theory: One-Loop Origins of Vector-Multiplet Kinetics in Type II Calabi–Yau Compactifications

The Emergence Proposal suggests that kinetic terms in effective theories of quantum gravity arise from integrating out non-perturbative states, and that this mechanism underlies several key Swampland constraints. We present evidence for this picture in Type II string theory compactified on Calabi–Yau manifolds. Across different limits of moduli space, we show that the full vector-multiplet kinetic terms, encoded in the prepotential, can be reinterpreted as one-loop effects of massive non-perturbative states. At large complex structure, the leading “tree-level’’ part of the prepotential acquires an emergent origin, arising from the ultraviolet modes of a heavy tower of states at one-loop. We also discuss the behavior at more exotic type II₀ loci in moduli space and its possible consequences for the Swampland Distance Conjectures.