AI 中文总结
本研究推导dS时空中带电标量场的单圈标量QED有效作用量，发现其可退化为闵可夫斯基或纯dS时空对应结果，还揭示外部场影响下引力常数演化及原初磁产生的可能机制。
AI 中文摘要
在电磁场与de Sitter（dS）时空共同作用下，粒子产生与真空极化可非微扰地探测量子电动力学（QED）和量子引力效应。通过对in-out形式化应用γ函数正规化，我们得到dS时空中均匀电场与平行磁场下带电标量场的单圈有效作用量，其为固有时积分表示形式。该作用量在闵可夫斯基时空极限下退化为单圈标量QED Weisskopf-Schwinger有效作用量，在纯dS时空极限下退化为纯dS时空的单圈有效作用量。在仔细考虑不同极限情形后，一个引人注目的结果涉及纯强电场极限下耦合常数的有效强度。我们的研究为外部场影响下牛顿引力常数的演化提供了进一步证据。值得注意的是，对有效势的分析表明，依赖于非最小耦合阈值的真空极化振幅领头阶贡献，会给出磁场的非零真空期望值。该机制在膨胀的早期dS阶段产生大磁场，这可能暗示原初磁产生的存在。
英文摘要
Particles creation and vacuum polarization under the influence of both an electromagnetic field and a de~Sitter (dS) spacetime nonperturbatively probes quantum electrodynamics (QED) and quantum gravitational effects. By applying the gamma-function regularization to the in-out formulation, we find the exact one-loop effective action in the proper-time integral representation for a charged scalar field in a uniform electric field and a parallel magnetic field in a dS spacetime. It reduces to the one-loop scalar QED Weisskopf-Schwinger effective action in the limit of Minkowski spacetime and the one-loop effective action in the pure dS spacetime. After carefully considering the different limiting cases, a striking result concerns the effective strengths of the coupling constants in the pure strong electric field limit. Our study provides further evidence for evolution of Newton's gravitational constant under the influence of the external fields. Remarkably, the analysis of the effective potential shows that the leading order contributions to the vacuum polarization amplitude, depending on the nonminimal coupling threshold, give a nonzero vacuum expectation value of the magnetic field. This mechanism generates a large magnetic field in the early dS stage of the expansion that may imply primordial magnetogenesis.
Comments20 pages
