Field Theory of Superstring and Heterotic String

超弦和异质弦的场论

• 批准号: 02640225
• 负责人: KUGO Taichi
• 金额: $ 1.15万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02640225/
• 关键词: String field theory; Target space duality; Gauge transformation; 3 Dimensional gravity; Renormalizability; Bethe-Salpeter equation; pi meson; Ward-Takahashi identity; コンパクト化; SchwingerーDyson方程式; 非多項式閉弦場の理論; ユニタリ-化処法; BRS不変性; 1; N展開; カイラル対称性; String field theory; Target space duality; Gauge transformation; 3 Dimensional gravity; Renormalizability; Bethe-Salpeter equation; pi meson; Ward-Takahashi identity; コンパクト化; SchwingerーDyson方程式; 非多項式閉弦場の理論; ユニタリ-化処法; BRS不変性; 1; N展開; カイラル対称性

1. As a particular property of string, there is " target space duality" : for instance, the physics of the string on a torus space compe(ctified with radius R is the same as that on a torus with radius 1/R. This duality transformation R -> 1/R is known to be extended to the group 0(d, d ; Z)for the d-dimensional torus. I have shown in collaboration with B. Zwiebach that this 0(d, d ; Z)duality is essentially contained in the string field theory as a symmetry corresponding to particular gauge transformations.2. The fact is well-known that the pure gravity in 3 dimension is renormalizable. I have shown that the 3 dimensional gravity remains renormalizable even when matter fields are coupled to it, using 1IN expansion where N is the number of the matter fields. However, it turned out that a tachyon pole in the graviton propagator appears there. This implies that the used vacuum is unstable. I am still studying the implications and the method how to avoid this problem.3. In collaboration w … More ith Aoki, Bando and Mitchard, I have devised a method to cilcixlate the pion decay constant fpi using Higashijima, s improved ladder approximaiton to Bethe-Salpeter(BS)equation. We found that the Pagels-Stoker's approximate formula gives a rather good value for fpi. Using the similar approximaiton to BS equation, we also calculated the masses and decay constants of the lowest lying mesons in QCD such as rho, Ai and scalar mesons. The numerical results are found to reproduce the observed values surprisingly well. It was, however, discovered very receraly that the Higashijima approximation violates the chiral Ward-Takahashi(WT)identity. I have shown together with Michard that the chiral WT identity is preserved if the gluon momentum is used as the argument of the running coupling constant, and that it is necessary to use a non-local gauge with gauge parameter being a function of momentum in order for the scheme to be consistent with the ladder approximation. We have also confirmed that this consistent ladder approximation with non-local gauge reproduces almost the same numerical results for the physical quantities previously calculated. Less

1。作为字符串的特定属性，存在“目标空间双重性”：例如，圆环空间上的字符串物理学（用半径为r进行c tit与半径为1/r的圆环上的二重性转换r-> 1/r相同，该二重性转换率是0（D，d; z）的d -dd -dd -ddimensional decore（d; zw）。 z）双重性在弦场理论中与特定的量规转换相对应。繁殖物出现在那里。我们发现，Pagels-Stoker的近似公式对FPI具有相当高的价值。使用与BS方程相似的近似值，我们还计算了QCD中最低的介体的质量和衰减常数，例如Rho，AI和标量介子。发现数值结果可以很好地重现观察到的值。然而，发现广岛近似违反手性沃德 - 塔卡哈西（WT）身份非常有回收。我已经与Michard一起表明，如果使用Gluon动量作为运行耦合常数的参数，则保留手性WT身份，并且有必要使用具有量规参数的非局部量规为动量的函数，以使该方案与梯子近似保持一致。我们还确认，与非本地量规的这种一致的梯子近似可再现先前计算的物理量的数值结果几乎相同。较少的