13.06.2017 / 14:00 - 15:30 / Hamburg, building 1, seminar room 01

Special String Theory Seminar

Gromov-Witten invariants and instantons on complete intersection Calabi-Yau manifolds

Fabian Ruehle (Oxford U.)

Non-perturbative superpotential contributions feature prominently in many moduli stabilisation scenarios. In heterotic theories these arise among others from world-sheet instantons. Unfortunately, a result of Beasley and Witten states that, while each contribution is non-zero individually, the sum of all contributions vanish, thus rendering these terms ineffective for model building. Finding the instantons requires knowledge of the world-sheet embedding into the Calabi-Yau. Their number is counted by the so-called Gromov-Witten invariants which can be computed using mirror symmetry. We present an algebraic way of constructing these curves without mirror symmetry and use this explicit representation to confirm that the Beasley-Witten result can be avoided on quotients of complete intersection Calabi-Yaus.