量子涨落

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量子力學中,量子涨落英语quantum fluctuation。或量子真空涨落真空涨落)是在空间任意位置對於能量的暂时变化。[1]维尔纳·海森堡不确定性原理可以推導出這結論。

根據這原理的一種表述,能量的不確定性 \Delta E 與能量改變所需的時間 \Delta t ,兩者之間的關係式為[2]

\Delta E \Delta t \approx \frac{\hbar}{2\pi}

其中 \hbar約化普朗克常数

这意味著能量守恒定律好像被违反了,但是仅持续很短的时间。因此,在空間生成了由粒子反粒子组成的虚粒子对。粒子对借取能量而生成,又在短时间内湮灭归还能量。这些产生的虚粒子的物理效应是可以被测量的,例如,電子的有效電荷與裸電荷不同。從量子电动力学兰姆位移卡西米尔效应,可以觀測到這效應。

量子涨落对于宇宙结构的起源非常重要,可以解釋宇宙为什么會出現超星系團纖維狀結構這一類結構的问题:根据宇宙暴胀理论,宇宙初期是均匀的,均匀宇宙存在的微小量子涨落在暴胀之后被放大到宇宙尺度,成为最早的星系结构的种子。

场量子涨落[编辑]

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引用[编辑]

  1. ^ Browne, Malcolm W. New Direction in Physics: Back in Time. The New York Times. 1990-08-21 [2010-05-22]. "According to quantum theory, the vacuum contains neither matter nor energy, but it does contain fluctuations, transitions between something and nothing in which potential existence can be transformed into real existence by the addition of energy.(Energy and matter are equivalent, since all matter ultimately consists of packets of energy.) Thus, the vacuum's totally empty space is actually a seething turmoil of creation and annihilation, which to the ordinary world appears calm because the scale of fluctuations in the vacuum is tiny and the fluctuations tend to cancel each other out." 
  2. ^ Mandelshtam, Leonid; Tamm, Igor, The uncertainty relation between energy and time in nonrelativistic quantum mechanics, Izv. Akad. Nauk SSSR (ser. Fiz.). 1945, 9: 122–128 . English translation: J. Phys. (USSR) 9, 249–254 (1945).

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