We analyze the quantum Fisher information (QFI) for a particle detector coupled to a thermal electromagnetic field in the cosmic string spacetime. It is found that vacuum fluctuation, temperature, detector polarization and nontrivial spacetime topology affect the QFI. Vacuum fluctuation and temperature degrade QFI. When deficit angle parameter ν = 1 and detector is far away from the string, the results in free Minkowski spacetime are restored. When detector is close to the string, QFI can be effectively enhanced; specially when detector lies in the string and is not polarized along axial direction, the detector seems like a closed system, and QFI completely is not affected by the thermal electromagnetic fluctuation. For nonzero detector–string distance, QFI appears oscillatory behaviors as detector–string distance varies. In addition, this detector eventually evolves to a thermal state, which is not related to the initial state and other various parameters, which implies ...

中文翻译：

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宇宙弦时空中的量子Fisher信息

我们分析了在宇宙弦时空中耦合到热电磁场的粒子探测器的量子Fisher信息（QFI）。发现真空波动，温度，检测器极化和非平凡的时空拓扑会影响QFI。真空波动和温度会降低QFI。当赤角参数ν= 1且探测器距离弦远时，恢复自由Minkowski时空的结果。当检测器靠近琴弦时，可以有效提高QFI；特别是当检测器位于弦中且未沿轴向极化时，检测器看起来像是一个封闭的系统，并且QFI完全不受热电磁波动的影响。对于非零检测器串距离，随着检测器串距离变化，QFI出现振荡行为。此外，