The duality between heterotic string theory on a 2-torus and F-theory on an elliptically fibered K3 surface is one of the most groundbreaking results to emerge from the superstring revolution, being intimately related to all other known string dualities. Despite this, a precise map between the moduli spaces of the two theories is only known at special loci. In this talk I will propose a method to compute a general map between moduli spaces. Specifically, I will argue that applying Nekrasov’s instanton calculus to a torus-compactified probe little string theory permits an explicit construction of an elliptic fibration in terms of the Narain moduli of the heterotic string. I will also mention potential applications and future prospects for this work.
