Abelian Higgs cosmic strings: Small-scale structure and loops
Abelian Higgs cosmic strings: Small-scale structure and loops
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阿贝尔希格斯宇宙弦：小尺度结构和环
DOI：
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发表时间：
2008
期刊：
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通讯作者：
Neil Bevis
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文献类型：
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作者：
M. Hindmarsh;S. Stuckey;Neil Bevis
阿贝尔希格斯模型的经典晶格模拟用于研究宇宙弦网络中的小尺度结构和环分布。场论的应用保证了对小尺度物理的正确捕捉。结果证实了Polchinski和Rocha[29]对弦切矢量两点相关函数的解析预测，具有从弦心宽度到水平尺度的幂律。与Nambu-Goto模拟相比，对弦环大小分布的分析得出了非常低的数字密度，每视界体积为1阶。此外，我们的循环分布函数不支持Dubath等人得出的关于循环产生的详细分析预测。与我们的数据更一致的是基于环裂[32]的模型，加上恒定的能量损失率转化为大质量辐射。我们的研究结果显示了一个强大的能量损失机制，它允许弦网络在没有重力辐射的情况下扩展，但这不是由于弦宽度环的产生。从小尺度结构的证据出发，我们对弦网络的极低频模式的能量如何转化为规范辐射和希格斯辐射的高频模式的尺度分离问题提出了部分解释。我们提出了一幅弦网络演化的图像，它调和了Nambu-Goto和场论模拟之间的明显差异。
Classical lattice simulations of the Abelian Higgs model are used to investigate small-scale structure and loop distributions in cosmic string networks. Use of the field theory ensures that the small-scale physics is captured correctly. The results confirm analytic predictions of Polchinski and Rocha [29] for the two-point correlation function of the string tangent vector, with a power law from length scales of order the string core width up to horizon scale. An analysis of the size distribution of string loops gives a very low number density, of order 1 per horizon volume, in contrast with Nambu-Goto simulations. Further, our loop distribution function does not support the detailed analytic predictions for loop production derived by Dubath et al. [30]. Better agreement to our data is found with a model based on loop fragmentation [32], coupled with a constant rate of energy loss into massive radiation. Our results show a strong energy-loss mechanism, which allows the string network to scale without gravitational radiation, but which is not due to the production of string width loops. From evidence of small-scale structure we argue a partial explanation for the scale separation problem of how energy in the very low frequency modes of the string network is transformed into the very high frequency modes of gauge and Higgs radiation. We propose a picture of string network evolution, which reconciles the apparent differences between Nambu-Goto and field theory simulations.