标题： 大半径和弦统一 显示英文标题

标题： Large radii and string unification

摘要： 我们研究四维杂化弦模型中的强耦合效应，其中超对称通过大内部维度自发破缺，并与规范耦合的微扰统一一致。 这些效应导致与对偶理论相关的阈值：I型超弦理论或M理论。 在有一个大维度的情况下，我们发现这些阈值出现在场论统一尺度$\sim 10^{16}$ GeV 附近，为引力和规范相互作用的统一提供了一个有吸引力的场景。 我们还确定了M理论第十一维度的逆尺寸与四费米子有效算符变得重要的能量。 显示英文摘要

摘要： We study strong coupling effects in four-dimensional heterotic string models where supersymmetry is spontaneously broken with large internal dimensions, consistently with perturbative unification of gauge couplings. These effects give rise to thresholds associated to the dual theories: type I superstring or M-theory. In the case of one large dimension, we find that these thresholds appear close to the field-theoretical unification scale $\sim 10^{16}$ GeV, offering an appealing scenario for unification of gravitational and gauge interactions. We also identify the inverse size of the eleventh dimension of M-theory with the energy at which four-fermion effective operators become important.