arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 2009.00830hep-phhep-th
收藏

弱磁化介质中的胶子极化张量和色散关系

Gluon polarization tensor and dispersion relation in a weakly magnetized medium

Alejandro Ayala, Jorge David Castaño-Yepes, L. A. Hernández, Jordi Salinas, R. Zamora

摘要:

研究了单圈级弱磁化背景中胶子的偏振和色散性质。为此,我们给出了带电费米子传播子在弱场展开中的两种不同的推导,并利用此表达式计算了胶子极化张量的最低阶磁场修正。我们明确地表明,尽管它的笨重的外观,胶子极化张量是横向的规范不变性所需的。我们还表明,没有开发的三个偏振模式的磁质量和胶子沿光锥传播,尽管洛伦兹不变性是由于磁场的存在下丢失。通过与适用于磁场中所有阶次的胶子极化张量的表达式进行比较,证明了对应于有限胶子质量的第二解的存在性是虚假的,是场强度最低阶近似的假象.我们还研究了实胶子极化模的强度。我们的结论是,提供虚假的解决方案被丢弃,胶子的极化和色散特性的最低阶近似是好的,只要场强度是小的相比,圈费米子质量。

英文摘要:

We study the polarization and dispersion properties of gluons moving within a weakly magnetized background at one-loop order. To this end, we show two alternative derivations of the charged fermion propagator in the weak field expansion and use this expression to compute the lowest order magnetic field correction to the gluon polarization tensor. We explicitly show that, in spite of its cumbersome appearance, the gluon polarization tensor is transverse as required by gauge invariance. We also show that none of the three polarization modes develops a magnetic mass and that gluons propagate along the light cone, non withstanding that Lorentz invariance is lost due to the presence of the magnetic field. By comparing with the expression for the gluon polarization tensor valid to all orders in the magnetic field, the existence of a second solution, corresponding to a finite gluon mass, is shown to be spurious and an artifact of the lowest order approximation in the field strength. We also study the strength of the polarization modes for real gluons. We conclude that, provided the spurious solutions are discarded, the lowest order approximation to the gluon polarization and dispersion properties is good as long as the field strength is small compared to the loop fermion mass.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑