arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 0712.1667astro-phgr-qchep-ph
收藏

宇宙缺陷产生磁场的挑战

Challenges for creating magnetic fields by cosmic defects

Lukas Hollenstein, Chiara Caprini, Robert Crittenden, Roy Maartens

摘要:

我们分析了拓扑缺陷在辐射时代通过哈里森机制作为磁场源的可能性。本文详细推导了宇宙学扰动中一阶Harrison机制的相对论性,并指出它只对T ~ 0.2 keV以上的温度有效。我们的主要结果是,由缺陷产生的矢量度规扰动不能在线性顺序的物质流体中诱导涡度,从而排除了电流和磁场的产生。我们表明,各向异性应力的物质流体所需的源涡和磁场。我们的分析适用于任何一种纯粹通过引力相互作用传递涡旋的机制,因此也适用于暗物质或中微子。

英文摘要:

We analyse the possibility that topological defects can act as a source of magnetic fields through the Harrison mechanism in the radiation era. We give a detailed relativistic derivation of the Harrison mechanism at first order in cosmological perturbations, and show that it is only efficient for temperatures above T ~ 0.2 keV. Our main result is that the vector metric perturbations generated by the defects cannot induce vorticity in the matter fluids at linear order, thereby excluding the production of currents and magnetic fields. We show that anisotropic stress in the matter fluids is required to source vorticity and magnetic fields. Our analysis is relevant for any mechanism whereby vorticity is meant to be transferred purely by gravitational interactions, and thus would also apply to dark matter or neutrinos.

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。

↑