Multiple anomalous U(1)s in heterotic blow-ups

S Groot Nibbelink,H.P Nilles,M Trapletti

doi:10.1016/j.physletb.2007.07.007

Abstract

The existence of multiple anomalous U(1)s is demonstrated explicitly in a blow-up version of a heterotic Z3 orbifold. Another blow-up of the same orbifold supports further evidence for the type I/heterotic duality in four dimensions. It has a single anomalous U(1) which does not factorize universally. As multiple anomalous U(1)s as well as non-universal factorization have never been established on heterotic orbifolds explicitly, these findings might appear contradictory at first sight. Possible inconsistencies are avoided by reinterpreting a charged twisted state as a second non-universal localized axion. The mismatch between the charges of the orbifold and blow-up spectra is resolved by suitable field redefinitions. The anomaly of the field redefinitions corresponds to the difference of blow-up and heterotic orbifold anomalies.

Highlights

Introduction and resultsFor phenomenological applications of heterotic string compactifications it is important to know the number of anomalous U(1)s [1, 2]
Recent publications [7, 8] argued that the low energy limit of the heterotic string, i.e. super Yang–Mills (YM) theory coupled to supergravity, on general smooth Calabi–Yau(CY)s with U(1) bundle backgrounds multiple anomalous U(1)s are possible
We argue that all these discrepancies can be explained by suitable field redefinitions

Summary

Introduction and results

For phenomenological applications of heterotic string compactifications it is important to know the number of anomalous U(1)s [1, 2]. Recent publications [7, 8] argued that the low energy limit of the heterotic string, i.e. super Yang–Mills (YM) theory coupled to supergravity, on general smooth Calabi–Yau(CY)s with U(1) bundle backgrounds multiple anomalous U(1)s are possible. We reinterpret a charged twisted singlet on the orbifold, that drives the blow–up by taking Vacuum Expectation Value(VEV), as a localized axion It takes part in a non–universal GS anomaly cancellation, very much like twisted RR–axions in type–I models. The anomaly in these field redefinitions precisely corresponds to the difference between blow–up and heterotic orbifold anomalies. We first describe this procedure for C3/Z3 blow–up models with U(1) bundles in general. Together with the universal axion auni (4D dual to b2) it will take part in the GS mechanism of anomaly cancellation

Spectral matching

Type–I blow–up model