A heterotic standard model with B โ L symmetry and a stable proton
A heterotic standard model with B โ L symmetry and a stable proton
We consider heterotic Calabi-Yau compactifications with S(U(4) ร U(1)) background gauge fields. These models lead to gauge groups with an additional U(1) factor which, under certain conditions, can combine with hypercharge to a B โ L symmetry. The associated gauge boson is automatically super-massive and, hence, does not constitute a โฆ