In Quantum Mechanics, Nothingness Is the Potential To Be Anything

No matter how hard you try to empty a box, zero-point energy remains.

无论你多么努力地清空盒子，能量仍然为零。

Suppose you want to empty a box.

假设您想清空一个盒子。

Really, truly empty it.

真的，真的空了。

You remove all its visible contents, pump out any gases, and — applying some science-fiction technology — evacuate any unseeable material such as dark matter.

你可以去除其中所有可见的内容，抽出所有气体，并应用一些科幻技术来疏散任何不可见的物质，例如暗物质。

According to quantum mechanics, what’s left inside?

根据量子力学，里面还剩下什么？

It sounds like a trick question.

这听起来像是一个棘手的问题。

And in quantum mechanics, you know to expect a trick answer.

在量子力学中，你知道会得到一个巧妙的答案。

Not only is the box still filled with energy, but all your efforts to empty it have barely put a dent in the amount.

盒子不仅仍然充满能量，而且你为清空它所付出的努力也几乎没有减少能量的多少。

This unavoidable residue is known as ground-state energy, or zero-point energy.

这种不可避免的残留物被称为基态能量或零点能量。

It comes in two basic forms: The one in the box is associated with fields, such as the electromagnetic field, and the other is associated with discrete objects, such as atoms and molecules.

它有两种基本形式：盒子里的一种与场相关，例如电磁场，另一种与离散物体相关，例如原子和分子。

You may dampen a field’s vibrations, but you cannot eliminate every trace of its presence.

你可以抑制场的振动，但你无法消除它存在的每一个痕迹。

And atoms and molecules retain energy even if they’re cooled arbitrarily close to absolute zero.

原子和分子即使被任意冷却到接近绝对零，也会保留能量。

In both cases, the underlying physics is the same.

在这两种情况下，基本的物理原理是相同的。

Zero-point energy is characteristic of any material structure or object that is at least partly confined, such as an atom held by electric fields in a molecule.

零点能量是任何至少部分受限的材料结构或物体的特征，例如分子中电场所保持的原子。

The situation is like that of a ball that has settled at the bottom of a valley.

这种情况就像一个球落在了山谷的底部。

The total energy of the ball consists of its potential energy (related to position) plus its kinetic energy (related to motion).

球的总能量由其势能（与位置相关）加上其动能（与运动相关）组成。

To zero out both components, you would have to give a precise value to both the object’s position and its velocity, something forbidden by the Heisenberg uncertainty principle.

要将这两个分量归零，您必须为物体的位置和速度提供精确的值，这是海森堡不确定性原理所禁止的。

What the existence of zero-point energy tells you at a deeper level depends ultimately on which interpretation of quantum mechanics you adopt.

零点能量的存在在更深层次上告诉你什么最终取决于你采用哪种量子力学解释。

The only noncontentious thing you can say is that, if you situate a bunch of particles in their lowest energy state and measure their positions or velocities, you will observe a spread of values.

您可以说的唯一无争议的事情是，如果您将一堆粒子置于最低能量状态并测量它们的位置或速度，您将观察到值的分布。

Despite being drained of energy, the particles will look as if they’ve been jiggling.

尽管能量被耗尽，粒子看起来好像一直在摇晃。

In some interpretations of quantum mechanics, they really have been.

在量子力学的一些解释中，确实如此。

But in others, the appearance of motion is a misleading holdover from classical physics, and there is no intuitive way to picture what’s happening.

但在其他方面，运动的出现是经典物理学的误导性遗留物，并且没有直观的方法来描绘正在发生的事情。

Zero-point energy was first introduced by Max Planck in 1911.

零点能量由马克斯·普朗克于 1911 年首次提出。

After that, “it was Einstein, I think, who took it seriously for the first time,” said Peter Milonni of the University of Rochester, a theorist who studies the quantum vacuum.

在那之后，“我想，是爱因斯坦第一次认真对待这个问题，”罗切斯特大学研究量子真空的理论家彼得·米洛尼说。

Einstein and others invoked zero-point energy to explain numerous phenomena, including the subtle vibrations of molecules and crystal lattices, even in their lowest energy states, and the failure of liquid helium to condense into a solid at ordinary pressure, even at temperatures so low you would expect atoms to lock in place.

爱因斯坦和其他人援引零点能量来解释许多现象，包括分子和晶格的微妙振动，即使在最低能量状态下，以及液氦在常压下也无法凝结成固体，即使在温度如此低的情况下，原子会锁定在适当的位置。

Albert Einstein (left) with Max Planck in Berlin in November 1931.

1931 年 11 月，阿尔伯特·爱因斯坦（左）与马克斯·普朗克在柏林。

Linda Hall Library of Science, Engineering and Technology

琳达·霍尔科学、工程与技术图书馆

A recent example was published in 2025 by researchers at the European X-Ray Free-Electron Laser Facility near Hamburg, among other institutions.

汉堡附近的欧洲 X 射线自由电子激光设施和其他机构的研究人员于 2025 年发布了最近的一个例子。

They cooled iodopyridine, an organic molecule consisting of 11 atoms, almost to absolute zero and hammered it with a laser pulse to break its atomic bonds.

他们将碘吡啶（一种由 11 个原子组成的有机分子）冷却到几乎为零，并用激光脉冲对其进行锤击以打破其原子键。

The team found that the motions of the freed atoms were correlated, indicating that, despite its chilled state, the iodopyridine molecule had been vibrating.

研究小组发现，游离原子的运动是相关的，这表明，尽管碘吡啶分子处于冷冻状态，但它一直在振动。

“That was not initially the main goal of the experiment,” said Rebecca Boll , an experimental physicist at the facility.

“这最初并不是实验的主要目标，”该设施的实验物理学家丽贝卡·波尔 (Rebecca Boll) 说。

“It’s basically something that we found.”

“这基本上就是我们发现的东西。”

Perhaps the best-known effect of zero-point energy in a field was predicted by Hendrick Casimir in 1948, glimpsed in 1958, and definitively observed in 1997.

也许场中最著名的零点能量效应是由亨德里克·卡西米尔 (Hendrick Casimir) 在 1948 年预测的，并于 1958 年被瞥见，并于 1997 年被明确观测到。

Two plates of electrically uncharged material — which Casimir envisioned as parallel metal sheets, although other shapes and substances will do — exert a force on each other.

两块不带电的材料板——卡西米尔设想为平行的金属板，尽管其他形状和物质也可以——彼此施加力。

Casimir said the plates would act as a kind of guillotine for the electromagnetic field, chopping off long-wavelength oscillations in a way that would skew the zero-point energy.

卡西米尔说，这些板将充当电磁场的一种断头台，以扭曲零点能量的方式切断长波长振荡。

According to the most accepted explanation, in some sense, the energy outside the plates is higher than the energy between the plates, a difference that pulls the plates together.

根据最被接受的解释，在某种意义上，板块外部的能量高于板块之间的能量，这种差异将板块拉在一起。

Quantum field theorists typically describe fields as a collection of oscillators, each of which has its own zero-point energy.

量子场论学家通常将场描述为振荡器的集合，每个振荡器都有自己的零点能量。

There is an infinite number of oscillators in a field, and thus a field should contain an infinite amount of zero-point energy.

场中存在无限数量的振荡器，因此场应该包含无限量的零点能量。

When physicists realized this in the 1930s and ’40s, they at first doubted the theory, but they soon came to terms with the infinities.

当物理学家在 20 世纪 30 年代和 40 年代意识到这一点时，他们起初对这个理论表示怀疑，但很快就接受了无穷大。

In physics — or most of physics, at any rate — energy differences are what really matters, and with care physicists can subtract one infinity from another to see what’s left .

在物理学中——或者至少在大部分物理学中——能量差异才是真正重要的，只要小心，物理学家就可以用一个无穷大减去另一个无穷大，看看还剩下什么。

That doesn’t work for gravity, though.

但这对重力不起作用。

As early as 1946, Wolfgang Pauli realized that an infinite or at least gargantuan amount of zero-point energy should create a gravitational field powerful enough to explode the universe.

早在 1946 年，沃尔夫冈·泡利 (Wolfgang Pauli) 就意识到，无穷大或至少是巨大的零点能量应该会产生一个足以爆炸宇宙的引力场。

“All forms of energy gravitate,” said Sean Carroll , a physicist at Johns Hopkins University.

“所有形式的能量都会产生引力，”约翰·霍普金斯大学的物理学家肖恩·卡罗尔说。

“That includes the vacuum energy, so you can’t ignore it.” Why this energy remains gravitationally muted still mystifies physicists.

“这包括真空能量，所以你不能忽视它。”为什么这种能量在引力作用下保持沉默仍然让物理学家感到困惑。

In quantum physics, the zero-point energy of the vacuum is more than an ongoing challenge, and it’s more than the reason you can’t ever truly empty a box.

在量子物理学中，真空的零点能量不仅仅是一个持续的挑战，也不仅仅是你无法真正清空盒子的原因。

Instead of being something where there should be nothing, it is nothing infused with the potential to be anything.

它不是一个本来应该什么都没有的东西，而是一个充满了成为任何东西的潜力的东西。

“The interesting thing about the vacuum is every field, and therefore every particle, is somehow represented,” Milonni said.

“真空的有趣之处在于每个场，因此每个粒子，都以某种方式表示，”米洛尼说。

Even if not a single electron is present, the vacuum contains “electronness.” The zero-point energy of the vacuum is the combined effect of every possible form of matter, including ones we have yet to discover.

即使不存在任何电子，真空也包含“电子”。真空的零点能量是所有可能的物质形式的综合效应，包括我们尚未发现的物质。

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