发表机构
Ferdowsi University of Mashhad（马什哈德 Ferdowsi 大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文通过 T-对偶性推导玻色弦理论中 $\alpha'$ 阶的 tachy on-无质量耦合，构建最小基并确定参数，发现势能形式导致 tachy on 凝聚，生成反德西特时空。
AI 中文摘要
最近，有研究提出玻色弦理论的经典有效作用量应只包含具有偶数个 tachy on 场的耦合。我们采用 T-对偶性程序来推导 tachy on 与无质量场在 $\alpha'$ 阶（四导数阶）的此类耦合。我们首先观察到，通过对 tachy on 势项进行高阶导数场重定义，可以选择一个方案，在该方案中，除了 tachy on 势本身之外，所有剩余的耦合仅涉及 tachy on 和无质量场的协变导数。然后，我们构建了四导数阶此类耦合的最小基，由 14 个独立项组成。施加 T-对偶性将此集合缩减为 6 个非零耦合，用两个未固定参数表示。其中一个参数通过匹配零 tachy on 极限下的已知有效作用量来确定，而另一个参数则通过与四个 tachy on 顶点算子的球面级 S-矩阵元比较来固定。后一比较还确立了 tachy on 势中 $T^4$ 项的系数为正。值得注意的是，tachy on 质量项和该四次项与形式为 $(2/\alpha')(-1+\cos T)$ 的势一致，这意味着闭弦 tachy on 凝聚到势在 $T=\pi$ 处的最小值，从而产生具有宇宙学常数 $\Lambda =-4/\alpha'$ 的反德西特时空。
英文摘要
Recently, it has been proposed that the classical effective action of bosonic string theory should contain only couplings with an even number of tachyon fields. We employ the T-duality procedure to derive such couplings at order \(α'\) (four-derivative order) for the tachyon and massless fields. We first observe that, through higher-derivative field redefinitions of the tachyon potential term, one can choose a scheme in which, apart from the tachyon potential itself, all remaining couplings involve only covariant derivatives of the tachyon and the massless fields. We then construct a minimal basis of such couplings at four-derivative order, consisting of 14 independent terms. Imposing T-duality reduces this set to 6 nonzero couplings, expressed in terms of two unfixed parameters. One of these parameters is determined by matching to the known effective action in the zero-tachyon limit, while the other is fixed by comparison with the sphere-level S-matrix element of four tachyon vertex operators. This latter comparison also establishes that the coefficient of the \(T^4\) term in the tachyon potential is positive. Remarkably, the tachyon mass term and this quartic term are consistent with a potential of the form \((2/α')(-1+\cos T)\), which implies that the closed string tachyon condenses to the minimum of the potential at \(T=π\), thereby generating an Anti-de Sitter spacetime with cosmological constant \(Λ=-4/α'\).
Comments20 pages, Latex file, no figure,v2: References added; it appears in JHEP
