Standard Model-like D-brane models and gauge couplings

TL;DR

This paper constructs and analyzes intersecting D-brane models that replicate the Standard Model's matter content and gauge symmetry, exploring their gauge coupling constants and implications for string scale.

Contribution

It introduces new classes of non-supersymmetric Standard Model-like D-brane models and studies their gauge coupling dependence on compactification parameters.

Findings

String scale should be above 10^{14-15} GeV for model consistency.

Gauge couplings depend on moduli, string scale, and winding numbers.

Models can potentially match experimental gauge coupling values.

Abstract

We systematically search intersecting D-brane models, which just realize the Standard Model chiral matter contents and gauge symmetry. We construct new classes of non-supersymmetric Standard Model-like models. We also study gauge coupling constants of these models. The tree level gauge coupling is a function of compactification moduli, string scale, string coupling and winding number of D-branes. By tuning them, we examine whether the models can explain the experimental values of gauge couplings. As a result, we find that the string scale should be greater than $10^{14-15}$GeV if the compactification scale and the string scale are the same order.