Open heterotic strings in compactifications

Investigate open heterotic strings in compactified heterotic theories and characterize their non-perturbative contributions, including Shenker effects arising from Euclidean wrapped objects and broken gauge groups.

Background

The authors argue that compactifications enrich the non-perturbative landscape through wrapped Euclidean objects and gauge symmetry breaking, with evidence from Green and Rudra for 9D HE involving Euclidean worldlines on S¹ with Wilson lines.

They explicitly defer the systematic study of open heterotic strings in compactified settings to future work.

References

We leave the study of open heterotic strings in compactifications to future work.

— Open Strings and Heterotic Instantons (2407.20319 - Álvarez-García et al., 2024) in Section 5 (Other heterotic theories)

Another important open problem is to characterize---and possibly to compute---the non-perturbative corrections to the ${\mathcal N}=1$ superpotential.

— Unorientable supersymmetric compactifications of M-theory (2609.10272 - Melnikov et al., 9 Sep 2026) in Conclusion of Section 5, “Discussion”