Why Is CERN Making Antimatter?
CERN为什么要制造反物质？
Inside the world's only antimatter factory — where physicists create, trap, and now transport the most expensive substance in the universe to solve one of the biggest mysteries in physics: why do we exist at all?
走进世界唯一的反物质工厂——物理学家们在这里制造、捕获、甚至运输宇宙中最昂贵的物质，只为回答一个终极问题：我们为什么会存在？
⚛️ What Is Antimatter?
⚛️ 什么是反物质？
Every particle has a mirror twin with opposite charge. When they meet, both vanish in a flash of pure energy.
每个粒子都有一个电荷相反的"镜像双胞胎"。当它们相遇，双双湮灭，化为纯能量。
The Minus Sign That Changed Physics
改变物理学的那个负号
In 1928, Paul Dirac united special relativity with quantum mechanics. His equation had two solutions for an electron at rest: E = mc² and E = −mc². Rather than discard the negative solution, Dirac proposed it predicted a new particle — identical to the electron but with opposite charge. He called it the anti-electron, or positron. Just one year later, in 1932, Carl Anderson accidentally observed the first positron in a cloud chamber.
1928年，保罗·狄拉克将狭义相对论与量子力学统一在一个方程中。对于静止电子，方程给出两个解：E = mc² 和 E = −mc²。狄拉克没有丢弃这个负数解，而是大胆预言它对应一种全新粒子——质量与电子相同，电荷相反。他称之为反电子，即正电子。仅仅一年后的1932年，卡尔·安德森在云室实验中意外观测到了第一个正电子。
Why Antiparticles Must Exist
反粒子为什么必须存在
Quantum field theory revealed that particles aren't tiny billiard balls — they're excitations of quantum fields that permeate all of space. An electron is a ripple in the electron field. The equations that describe these fields require mirror-opposite excitations: same mass and spin, opposite charge. When particle and antiparticle overlap, the excitations cancel, the field returns to its ground state, and the mass converts to energy (photons) via E = mc². This is annihilation — the most violent process physics allows.
量子场论揭示了一个惊人事实：粒子并不是微小的台球，而是弥漫整个空间的量子场中的"涟漪"。电子是电子场中的一个激发态。描述这些场的方程必然要求存在"镜像激发"——质量和自旋相同，电荷相反。当粒子和反粒子重叠，激发相互抵消，场回到基态，质量通过 E = mc² 转化为能量（光子）。这就是湮灭——物理学允许的最剧烈的过程。
💥 The Big Bang Problem
💥 大爆炸之谜
If equal amounts of matter and antimatter were created, everything should have annihilated. We shouldn't be here.
如果大爆炸产生了等量的物质和反物质，一切都应该湮灭殆尽。我们根本不该存在。
Where Did All the Antimatter Go?
所有的反物质都去哪了？
In the first moments after the Big Bang, the universe was so hot that photons spontaneously produced particle-antiparticle pairs. Around 3 seconds later, the universe cooled enough that pair production stopped. If matter and antimatter were truly equal, every particle should have found its twin and annihilated — leaving behind nothing but radiation. This was called the Big Bang radiation catastrophe. Physicists even searched the sky for "hot spots" where matter and antimatter regions might collide, but found none. The asymmetry is real.
大爆炸后的最初时刻，宇宙温度极高，光子能自发产生正反粒子对。大约3秒后，宇宙冷却到对产生停止。如果物质和反物质真的完全对称，每个粒子都会找到它的"双胞胎"并湮灭——只留下辐射，什么都不会剩下。这被称为"大爆炸辐射灾变"。物理学家甚至搜索天空中物质与反物质区域碰撞产生的"热点"，但一无所获。不对称性是真实的。
The Lucky Survivors
幸运的幸存者
The cosmic microwave background tells us there were roughly 10⁸⁹ photons created during that initial annihilation — meaning roughly 10⁸⁹ matter-antimatter pairs. But the observable universe today contains about 10⁸⁰ ordinary matter particles. That means for every billion antimatter particles and billion matter particles, the annihilation was almost perfect — but one extra matter particle out of every billion survived. Every person, star, galaxy, and planet is made from those lucky one-in-a-billion survivors.
宇宙微波背景辐射告诉我们，最初的湮灭产生了大约10⁸⁹个光子，意味着曾有同样数量级的正反物质对。但今天可观测宇宙中只有约10⁸⁰个普通物质粒子。也就是说，每十亿个反物质粒子和十亿个物质粒子几乎完美湮灭——但每十亿个中多出来的那一个物质粒子幸存了下来。每个人、每颗恒星、每个星系、每颗行星，都是由那些十亿分之一的幸运儿构成的。
🪞 Breaking Symmetry
🪞 对称性破缺
Physicists believed nature was perfectly symmetric. Then Madame Wu proved the universe plays favorites.
物理学家曾深信自然是完美对称的。然后吴健雄证明了宇宙其实"偏心"。
The Three Sacred Symmetries
三大"神圣"对称性
By the 1950s, physicists believed all interactions obeyed three fundamental symmetries: Charge (C) — swap positive and negative charges, nothing changes. Parity (P) — mirror-reflect everything, nothing changes. Time reversal (T) — run the clock backwards, nothing changes. Combined, CPT symmetry is built into the very structure of special relativity. If CPT breaks, our best theories — quantum field theory and the Standard Model — come crashing down with it.
到1950年代，物理学家相信所有相互作用都遵循三大基本对称性：电荷对称(C)——交换正负电荷，物理规律不变。宇称对称(P)——镜像反转一切，物理规律不变。时间反演对称(T)——让时间倒流，物理规律不变。三者组合的CPT对称性深植于狭义相对论的根基之中。如果CPT被打破，我们最好的理论——量子场论和标准模型——都将轰然倒塌。
Madame Wu Shatters the Mirror
吴健雄：打碎那面镜子
In 1956, Tsung-Dao Lee and Chen Ning Yang realized no one had tested parity in the weak nuclear force. Experimentalist Chien-Shiung Wu took on the challenge, canceling trips and working through holidays. Using cobalt-60 nuclei aligned by magnetic fields, she measured the direction of emitted electrons. If parity held, 50% should go each way. She found 60% went in one direction — proving the universe distinguishes left from right. Wolfgang Pauli had bet heavily against this result: "I do not believe that the Lord is a weak left-hander." He lost. Lee and Yang won the 1957 Nobel Prize, but Wu's name was left off — what Nobel laureate Jack Steinberger called "the biggest mistake in the Nobel Committee's history."
1956年，李政道和杨振宁意识到还没有人在弱核力中检验过宇称守恒。实验物理学家吴健雄接受了挑战，取消旅行，假期无休地投入工作。她用磁场排列钴-60原子核的自旋，测量释放电子的方向。如果宇称守恒，两个方向各占50%。结果她发现60%的电子偏向一个方向——证明宇宙能区分左和右。沃尔夫冈·泡利曾信誓旦旦打赌反对这个结果："我不相信上帝是一个弱左撇子。"他输了。李政道和杨振宁获得了1957年诺贝尔物理学奖，但吴健雄的名字被遗漏了——诺贝尔奖得主杰克·斯坦伯格称之为"诺贝尔委员会历史上最大的错误"。
The Standard Model Isn't Enough
标准模型远远不够
After parity fell, physicists hoped the combined charge-parity (CP) symmetry would hold. It didn't — CP violation was discovered in 1964. In 1973, Kobayashi and Maskawa found a way to explain all observed CP violation within the Standard Model while preserving CPT. But here's the catch: their mechanism can only account for an asymmetry of 10⁻¹⁸ — a billion times too small to explain why we exist. The ingredients are there, but not in large enough quantities. This means there is almost certainly new physics beyond the Standard Model waiting to be discovered.
宇称破缺之后，物理学家寄希望于组合的电荷-宇称(CP)对称性仍然成立。然而CP破缺在1964年也被发现了。1973年，小林诚和益川敏英找到了一种方法，在保持CPT对称的同时解释所有观测到的CP破缺。但关键问题是：他们的机制只能解释10⁻¹⁸量级的不对称——比解释我们存在所需的小了十亿倍。成分是有的，但量远远不够。这几乎可以确定，标准模型之外还有全新的物理学等待被发现。
🏭 The Antimatter Factory
🏭 反物质工厂
At the southern edge of the LHC, protons are smashed into iridium at 99.93% the speed of light to create anti-protons.
在大型强子对撞机的南缘，质子以99.93%光速撞击铱靶，产生反质子。
Smashing Protons Into Existence
撞出来的反物质
Protons from the Proton Synchrotron are accelerated to 99.93% the speed of light (26 GeV) and slammed into an iridium rod just 3 mm in diameter. Iridium is chosen because it's the second densest element — maximum nuclei packed into minimum space. When a proton penetrates a nucleus and hits one of its quarks, the collision creates a shower of quark-antiquark pairs. Occasionally, two anti-up quarks and one anti-down quark find each other and bind together to form an anti-proton — all within 10⁻²³ seconds. Each shot produces trillions of collisions, yielding about 40 million anti-protons every two minutes.
来自质子同步加速器的质子被加速到99.93%光速（26 GeV），然后猛烈撞击一根直径仅3毫米的铱棒。选择铱是因为它是密度第二高的元素——在最小空间内塞满了最多的原子核。当质子穿透原子核击中其中一个夸克时，碰撞产生一阵夸克-反夸克对的"粒子雨"。偶尔，两个反上夸克和一个反下夸克相遇并结合，形成一个反质子——整个过程在10⁻²³秒内完成。每次撞击产生数万亿次碰撞，每两分钟产生约4000万个反质子。
Slowing Down the Speed Demons
让"闪电"慢下来
Anti-protons emerge at 96% the speed of light — far too fast for experiments. The Antiproton Decelerator ring slows them to 10% of light speed using electric fields. But that's still 100 million km/h. Originally, they fired the beam at a plastic foil, which annihilated 99.9% of all anti-protons — only 0.1% survived, slow enough to use. In 2015–2016, a secondary ring called ELENA was installed, elegantly slowing anti-protons to 1.5% the speed of light (16.2 million km/h) with 86% efficiency.
反质子以96%光速飞出——对实验来说太快了。反质子减速器环利用电场将它们减速到10%光速，但这仍然是每小时1亿公里。最初的办法相当粗暴：把粒子束射向一片塑料薄膜，99.9%的反质子被湮灭，只有0.1%幸存下来，速度才够慢。2015-2016年，二级减速环ELENA投入使用，优雅地将反质子减速到1.5%光速（每小时1620万公里），效率高达86%。
The Most Expensive Substance on Earth
地球上最贵的物质
How much does antimatter cost? $1 billion per gram? Way too cheap. $100 billion? Still missing three zeros. The true cost is at least $100 trillion per gram — and that's probably an underestimate. In 25 years of operation, CERN's factory has produced roughly 10¹¹ anti-protons total. A single gram would require 10²³. At the current rate, producing one gram would take longer than the age of the universe.
反物质多贵？10亿美元一克？便宜太多了。1000亿美元？还差三个零。真实成本至少是每克100万亿美元——这可能还是低估了。CERN的工厂运行25年，总共只产生了约10¹¹个反质子。而一克需要10²³个。按目前的速度，生产一克需要的时间比宇宙年龄还长。
🧲 Trapping the Impossible
🧲 捕获不可能
How do you store a substance that annihilates on contact with anything? Superconducting magnets and a vacuum colder than outer space.
如何储存一种碰到任何东西就湮灭的物质？超导磁体加上比太空还冷的真空。
A Cage Made of Fields
由"力场"构成的牢笼
The Penning trap is a vacuum tube surrounded by a superconducting magnet that confines charged particles to the center, while electrodes at each end act as electric "caps" preventing escape. The entire tube is cooled to 4 Kelvin (−269°C), causing residual gas to freeze out and creating a vacuum comparable to outer space. Inside this near-perfect void, anti-protons have nothing to annihilate with and nowhere to go. The TRAP experiment at CERN used this to measure the charge-to-mass ratio of anti-protons — finding it equal to the proton's to one part in 10 billion.
彭宁阱是一根真空管，外围环绕超导磁体将带电粒子限制在中心，两端的电极充当电"帽"防止逃逸。整根管子冷却到4开尔文（-269°C），残余气体冻结析出，创造出堪比太空的真空度。在这个近乎完美的真空中，反质子既无物可湮灭，也无处可逃。CERN的TRAP实验利用它测量了反质子的荷质比——发现与质子一致，精度达到百亿分之一。
Precision Tests of Antimatter
反物质的精密检验
In 2017, the BASE experiment measured the anti-proton's magnetic moment and found it equal and opposite to the proton's within their measurement accuracy. So far, every test has confirmed that matter and antimatter behave identically in every measurable way — exactly as predicted. But there's one force that hadn't been directly tested: gravity. And gravity doesn't have to obey CPT symmetry, because it doesn't fully obey special relativity. That makes it the most promising place to look for new physics.
2017年，BASE实验测量了反质子的磁矩，发现在测量精度范围内与质子完全相等且方向相反。到目前为止，每一次测试都证实物质和反物质在所有可测量的方面表现完全相同——恰如预测。但有一种力还没有被直接检验：引力。而引力不必遵守CPT对称性，因为它并不完全遵循狭义相对论。这使得引力成为寻找新物理学最有希望的方向。
⚗️ Making Anti-Atoms
⚗️ 制造反原子
To test gravity, you need neutral anti-atoms. Making them is one of the most complex processes in all of physics.
要测试引力，你需要中性的反原子。制造反原子是物理学中最复杂的过程之一。
The Shortest-Lived Atom
寿命最短的"原子"
The GBAR experiment takes a particularly ingenious approach. First, they accelerate electrons to 99.9% the speed of light and fire them at a tungsten target, producing positrons through a cascade of bremsstrahlung radiation and pair production. (The radiation from this step is so intense that entering the room while it's running would be lethal in 10 seconds.) About 100 million positrons are accumulated, then fired at porous silicon dioxide films where they capture electrons to form positronium — an exotic "atom" where an electron and positron orbit each other like a binary star. It lasts just 142 nanoseconds before annihilating.
GBAR实验采用了一种极其精巧的方法。首先，将电子加速到99.9%光速并射向钨靶，通过韧致辐射和对产生的级联过程产生正电子。（这一步产生的辐射极其强烈，如果在运行时进入房间，10秒内就会致命。）大约1亿个正电子被积累起来，然后射向多孔二氧化硅薄膜，在那里它们捕获电子形成电子偶素——一种奇异的"原子"，电子和正电子像双星系统一样互相环绕。它只存在142纳秒就会湮灭。
Building the Impossible Atom
建造不可能的原子
With positronium lasting only 142 nanoseconds, timing is everything. Anti-protons from ELENA are fired through the positronium cloud at precisely the right moment. Out of around 3 million anti-protons passing through, roughly one to a few steal a positron from the positronium to create anti-hydrogen — one anti-proton orbited by one positron. CERN first achieved this in 1995, but those early anti-atoms survived only 40 billionths of a second. The breakthrough came when magnetic traps (using anti-hydrogen's tiny magnetic moment) managed to hold them long enough for experiments.
电子偶素只能存在142纳秒，时间就是一切。来自ELENA的反质子在精确的时刻穿过电子偶素云。大约300万个反质子中，只有一到几个能从电子偶素中"偷走"一个正电子，形成反氢——一个反质子被一个正电子环绕。CERN在1995年首次实现了这一壮举，但那些早期的反原子只存活了百亿分之四秒。突破性进展来自磁阱技术——利用反氢微弱的磁矩将其束缚住，使其存活到足够进行实验的时间。
🍎 Does Antimatter Fall Up?
🍎 反物质会"上升"吗？
In the 1950s, physicists seriously entertained the idea of anti-gravity. Now they're finally testing it.
1950年代，物理学家曾认真考虑过"反引力"的可能性。现在他们终于可以检验了。
Antimatter Falls Down (Probably)
反物质也会下落（大概是）
In 2023, the ALPHA-g experiment weakened the magnetic trap holding anti-hydrogen atoms and watched where they escaped. If antimatter falls down like normal matter, more atoms should escape through the bottom. That's exactly what happened — ruling out anti-gravity. They measured gravitational acceleration at 75% of normal, with error bars of +13%/−16%. Possibly consistent with normal gravity, but the measurement is still rough. ALPHA-g can cool anti-hydrogen to about 0.5 Kelvin — impressive, but not precise enough.
2023年，ALPHA-g实验逐渐减弱束缚反氢原子的磁阱，观察它们从哪里逃逸。如果反物质像普通物质一样下落，应该有更多原子从底部逃出。结果正是如此——排除了反引力。他们测量的引力加速度为正常值的75%，误差范围为+13%/-16%。可能与正常引力一致，但测量还很粗糙。ALPHA-g能将反氢冷却到约0.5开尔文——很厉害，但精度还不够。
Watching a Single Anti-Atom Fall 20 cm
看一个反原子下落20厘米
GBAR aims for 1% precision (ultimately 1 in 100,000) by making anti-hydrogen ions — one anti-proton with two positrons. Because the ion is charged, it can be electromagnetically trapped and cooled to 10 micro-Kelvin using laser-cooled beryllium ions: 50,000 times colder than ALPHA-g. Then a laser pulse strips one positron, leaving a neutral anti-hydrogen atom that simply falls about 20 cm. At that temperature and distance, the fall can be timed precisely enough for a 1% measurement. All the complexity — the particle accelerator, the positronium converter, the ion cooling — exists just to watch one anti-atom fall 20 cm.
GBAR的目标是实现1%的精度（最终达到十万分之一），方法是制造反氢离子——一个反质子带两个正电子。因为离子带电，可以用电磁阱捕获，再利用激光冷却的铍离子将其冷却到10微开尔文：比ALPHA-g冷5万倍。然后用激光脉冲剥离一个正电子，留下一个中性反氢原子，让它自由下落约20厘米。在这个温度和距离下，下落时间可以被精确计时，足以实现1%精度的测量。所有的复杂性——粒子加速器、电子偶素转换器、离子冷却——都只是为了看一个反原子下落20厘米。
📦 Portable Antimatter
📦 便携反物质
On March 24, 2026, CERN loaded antimatter onto a truck and drove it around. Angels and Demons wasn't that far off.
2026年3月24日，CERN把反物质装上卡车运走了。《天使与魔鬼》的情节也没差太远。
Storing the Unstoppable for Two Years
将"不可阻挡"之物存储两年
The BASE experiment built a self-contained Penning trap with its own power supply, cooling system, and two anti-proton storage holds. Their record: 614 days of continuous anti-proton storage — nearly two years of keeping the most volatile substance in the universe from touching matter. This cracked the code for portability: if you can store it for years in a box, you can put that box on a truck.
BASE实验建造了一个自给自足的彭宁阱，配备独立电源、冷却系统和两个反质子储存腔。他们的记录：连续存储反质子614天——将宇宙中最"暴烈"的物质与普通物质隔离了近两年。这破解了便携性的密码：如果你能把它在盒子里存两年，你就能把盒子放上卡车。
Antimatter Goes on a Road Trip
反物质上路了
On March 24, 2026, a crane lifted an 800 kg trap out of the antimatter factory and loaded it onto a truck. Filled with 92 anti-protons, the truck drove a 10 km loop around CERN. This proof-of-concept opens the door to distributing antimatter to labs worldwide. "Everyone who has a good idea what we could do with these particles will get these particles," said the team. The vision: a global network fed by CERN's factory, shipping antimatter to ambitious experiments everywhere.
2026年3月24日，一台起重机将一个800公斤的阱从反物质工厂中吊出，装上卡车。装载着92个反质子，卡车在CERN周围行驶了10公里。这个概念验证为向全球实验室分发反物质打开了大门。团队表示："任何对这些粒子有好想法的人都将得到这些粒子。"愿景是：以CERN工厂为中心，向全球各地的实验室运送反物质。
💣 The Vatican Simulation
💣 梵蒂冈模拟
Angels and Demons meets nuclear physics. What would an eighth of a gram of antimatter actually do?
当《天使与魔鬼》遇上核物理：八分之一克反物质到底能干什么？
0.125 Grams vs. the Vatican
0.125克 vs 梵蒂冈
The Veritasium team simulated the Angels and Demons scenario: detonating ⅛ gram of antimatter at Vatican City. The fireball — reaching 100 million °C — would instantly vaporize everything nearby into plasma. The blast releases about 22 trillion joules, equivalent to 36% of the Hiroshima bomb. St. Peter's Basilica wouldn't stand a chance. Third-degree burns extend across a wide radius. But here's the reality check: to make ⅛ gram, CERN's factory would have to run longer than the age of the universe. Their total 25-year output, annihilated all at once, would produce enough energy to heat 1 ml of water by 1°C.
Veritasium团队模拟了《天使与魔鬼》中的场景：在梵蒂冈引爆⅛克反物质。火球温度达到1亿°C，瞬间将周围一切气化为等离子体。爆炸释放约22万亿焦耳能量，相当于广岛原子弹的36%。圣彼得大教堂毫无生还可能。三度烧伤范围覆盖很大区域。但现实是：要制造⅛克反物质，CERN的工厂需要运行比宇宙年龄还长的时间。他们25年的总产量，即使一次性全部湮灭，产生的能量只够把1毫升水加热1°C。
You Are an Antimatter Factory
你自己就是一座反物质工厂
Bananas contain trace amounts of radioactive potassium-40. Roughly every 75 minutes, one of those atoms decays and releases a positron. To match CERN's output in terms of antiparticles, you'd need about a billion bananas. But even without bananas, your body contains trace radioactive materials that produce antimatter. One estimate puts the average human at about 180 positrons per hour. You've been your own little antimatter factory all along.
香蕉含有微量的放射性钾-40。大约每75分钟，其中一个原子衰变并释放一个正电子。要在反粒子数量上匹配CERN的产量，你需要大约10亿根香蕉。但即使不吃香蕉，你体内的微量放射性物质也在产生反物质。据估计，普通人每小时产生约180个正电子。你自己一直就是一座小型反物质工厂。
"Everything we see around us today is a descendant of those lucky one in a billion particles."
"我们今天看到的一切，都是那十亿分之一的幸运粒子的后代。"
— Veritasium
— Veritasium