真空能

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Field and particle theories
场合粒子理论
Quantum field theory considers the vacuum ground state not to be completely empty, but to consist of a seething mass of virtual particles and fields. Since these fields do not have a permanent existence, they are called vacuum fluctuations. In the Casimir effect, two metal plates can cause a change in the vacuum energy density between them which generates a measurable force.
量子场论考虑的真空基态并不是完全空的，而是有一些沸腾的虚例子和场的质量。既然这些场并不稳定存在，因此被称为真空涨落。在卡西密尔效应中，两块金属平板，可以引起板间的真空能量密度的改变，从而产生一个可测量的力。

Some believe that vacuum energy might be the "dark energy" (also called quintessence) associated with the cosmological constant in General relativity, thought to be similar to a negative force of gravity. Observations that the expanding Universe appears to be accelerating seem to support the Cosmic inflation theory —first proposed by Alan Guth (1981) — in which the nascent Universe passed through a phase of exponential expansion driven by a negative vacuum energy density (positive vacuum pressure).
一些人相信真空能可能是“暗能量”（也叫做第五物质），这种能量和广义相对论中的宇宙常数有联系，并被认为是负引力。观测发现，我们这个宇宙正在加速膨胀，这支持了Alan Guth在1981年提出的暴涨宇宙理论。暴涨宇宙理论指出，在宇宙初生的时候，经过一个由负真空能量密度（正的真空压）所推动的指数型的膨胀。

Implications
含义
Vacuum energy has a number of consequences. Vacuum fluctuations are always created as particle/antiparticle pairs. The creation of these virtual particles" near the event horizon of a black hole has been hypothesized by physicist Stephen Hawking to be a mechanism for the eventual "evaporation" of black holes. The net energy of the universe remains zero so long as the particle pairs annihilate each other within Planck time. If one of the pair is pulled into the black hole before this, then the other particle becomes "real" and energy/mass is essentially radiated into space from the black hole. This loss is cumulative and could result in the black hole's disappearance over time. The time required is dependent on the mass of the black hole, but could be on the order of 10^100 years for large solar-mass black holes.
真空能有一些结果。真空涨落一直产生粒子和反粒子对。对于在黑洞的世界线附件产生的虚粒子，物理学家霍金假设了这是最终的黑洞蒸发的机制。在普朗克时间内，粒子对湮灭后宇宙的净能量为零。如果一对粒子中的某个在湮灭前落入黑洞，那么剩下的这个成为“实”的粒子，并且能量从黑洞辐射到空间中。时间是与黑洞的质量相关的，对于大恒星质量的黑洞，这个时间需要10^100年量级。
The Grand unification theory predicts a non-zero cosmological constant from the energy of vacuum fluctuations. Examining normal physical processes with knowledge of these field phenomena can lead to an interesting insight in electrodynamics. During discussions of perpetual motion, the topic of vacuum energy usually encourages serious inquiries.
从真空涨落，大统一理论预测了一个非零的宇宙常数。用现有的知识检查这些正常的物理过程，可以导致对电动力学的一个有趣的洞察。在永动机制的讨论中，真空能量这个主题通常是严肃的。

History
历史
In 1934, Georges Lemaître used an unusual perfect-fluid equation of state to interpret the cosmological constant as due to vacuum energy. In 1973, Edward Tryon proposed that the Universe may be a large scale quantum mechanical vacuum fluctuation where positive mass-energy is balanced by negative gravitational potential energy. During the 1980s, there were many attempts to relate the fields that generate the vacuum energy to specific fields that were predicted by the Grand unification theory, and to use observations of the Universe to confirm that theory. These efforts had failed so far, and the exact nature of the particles or fields that generate vacuum energy, with a density such as that required by the Inflation theory, remains a mystery.
在1934年，Georges Lemaître 用一个不寻常的理想流体的状态方程解释宇宙常数是由真空能量引起的。在1973年，Edward Tryon 提出一个假设，宇宙可以是一大尺度的量子力学的真空涨落，这里正的质能是由负的引力势能所平衡。在20世纪80年代，有些人尝试把产生真空能的场和由大统一理论预测的场联系起来，并用宇宙的观察数据来验证这个理论。这些努力到目前为止都失败了，到现在，我们仍然没有能够揭开，产生真空能的粒子和场的本质，暴涨理论所要求的能量密度这些神秘的面纱。