量子加密競(jìng)賽方興未艾，中國(guó)已領(lǐng)先一步

SAN FRANCISCO — The world’s leading technology companies, from Google to Alibaba in China, are racing to build the first quantum computer, a machine that would be far more powerful than today’s computers.

舊金山——從谷歌到中國(guó)的阿里巴巴，世界上領(lǐng)先的科技企業(yè)都在競(jìng)相建造第一臺(tái)量子計(jì)算機(jī)，它將比今天的計(jì)算機(jī)強(qiáng)大得多。

This device could break the encryption that protects digital information, putting at risk everything from the billions of dollars spent on e-commerce to national secrets stored in government databases.

量子設(shè)備可以破解用于保護(hù)數(shù)字信息的加密，使所有的數(shù)字信息面臨危險(xiǎn)，從數(shù)十億美元的電子商務(wù)支付，到存儲(chǔ)在政府?dāng)?shù)據(jù)庫(kù)的國(guó)家機(jī)密。

An answer? Encryption that relies on the same concepts from the world of physics. Just as some scientists are working on quantum computers, others are working on quantum security techniques that could thwart the code-breaking abilities of these machines of the future.

有應(yīng)對(duì)的辦法嗎?那就是依賴于物理世界相同概念的加密。正如一些科學(xué)家在研究量子計(jì)算機(jī)一樣，另一些科學(xué)家也在研究量子安全技術(shù)，這種技術(shù)可以阻止這些未來(lái)機(jī)器的密碼破譯能力。

It is a race with national security implications, and while building quantum computers is still anyone’s game, China has a clear lead in quantum encryption. As it has with other cutting-edge technologies, like artificial intelligence, the Chinese government has made different kinds of quantum research a priority.

這是一場(chǎng)可能影響國(guó)家安全的競(jìng)賽，盡管建造量子計(jì)算機(jī)仍是大家都在干的事情，但中國(guó)在量子加密方面已明顯領(lǐng)先。與中國(guó)在人工智能等其他尖端技術(shù)上的做法一樣，政府已經(jīng)把各種量子研究列為重點(diǎn)。

“China has a very deliberate strategy to own this technology,” said Duncan Earl, a former researcher at Oak Ridge National Laboratory who is president and chief technology officer of Qubitekk, a company that is exploring quantum encryption. “If we think we can wait five or 10 years before jumping on this technology, it is going to be too late.”

“中國(guó)對(duì)擁有這項(xiàng)技術(shù)有一個(gè)經(jīng)過(guò)深思熟慮的戰(zhàn)略，”鄧肯·厄爾(Duncan Earl)說(shuō)，他曾是橡樹(shù)嶺國(guó)家實(shí)驗(yàn)室(Oak Ridge National Laboratory)的研究員，現(xiàn)在是探索量子加密技術(shù)的Qubitekk公司的總裁兼首席技術(shù)官。“如果我們認(rèn)為我們可在加入這項(xiàng)技術(shù)之前等個(gè)五年、十年的話，那將太晚了。”

Quantum computing is based on quantum mechanics, the science that explains the strange behavior exhibited by extremely small particles of matter.

量子計(jì)算以量子力學(xué)為基礎(chǔ)，量子力學(xué)是解釋極小的物質(zhì)粒子所表現(xiàn)出的奇怪行為的科學(xué)。

With traditional computers, transistors store “bits” of information, and each bit is either a 1 or a 0. Those are the fundamental slices of data that tell a computer what to do.

在傳統(tǒng)計(jì)算機(jī)中，晶體管存儲(chǔ)信息的“位”，每個(gè)位不是1就是0。這些是告訴計(jì)算機(jī)該如何操作的基本數(shù)據(jù)單位。

When some types of matter are extremely small or extremely cold, they behave differently. That difference allows a quantum bit, or qubit, to store a combination of 1 and 0. Two qubits can hold four values at once. As the number of qubits grows, a quantum computer becomes exponentially more powerful.

當(dāng)物質(zhì)非常小或非常冷時(shí)，它們會(huì)發(fā)生不同的行為。這種差異允許一個(gè)量子位(qubit)存儲(chǔ)1和0的組合。兩個(gè)量子位可以同時(shí)保存四個(gè)值。隨著量子位數(shù)量的增長(zhǎng)，量子計(jì)算機(jī)的計(jì)算能力指數(shù)式地增長(zhǎng)。

Like quantum computing, quantum encryption relies on the nonintuitive behavior of very small objects. The codes that keep data secret are sent by photons, the tiniest particle of light. With the right equipment it is easy to tell if they have been tampered with, not unlike the seal on an aspirin bottle. If carried out properly, the technique could be unbreakable.

和量子計(jì)算一樣，量子加密技術(shù)依賴于非常小的物體的非直覺(jué)行為。保護(hù)數(shù)據(jù)秘密的密碼是通過(guò)光子發(fā)出的，光子是最小的光粒子。使用合適的設(shè)備，就很容易判斷密碼是否被擅自改動(dòng)過(guò)，這就像是阿司匹林藥瓶上的封條是否破損。如果使用得當(dāng)，量子加密技術(shù)可能是牢不可破的。

There is no guarantee that a viable quantum encryption network could be built over long distances. But if it does happen, China’s willingness to experiment and put government, academic and commercial resources behind the effort could have a big payoff.

不能保證一個(gè)可行的量子加密網(wǎng)絡(luò)可以在長(zhǎng)距離上建立起來(lái)。但如果能夠建立的話，中國(guó)愿意進(jìn)行試驗(yàn)，并將政府、學(xué)術(shù)和商業(yè)資源投入其中的做法，可能會(huì)帶來(lái)巨大回報(bào)。

The country has invested tens of millions of dollars building networks that can transmit data using quantum encryption. Last year, a Chinese satellite named Micius, after an ancient philosopher, managed a video call between Beijing and Vienna using quantum encryption. A dedicated quantum communication network between Beijing and Shanghai was also put into operation last year, after four years of planning and construction.

中國(guó)已經(jīng)在建設(shè)使用量子加密傳輸數(shù)據(jù)的網(wǎng)絡(luò)上投入了數(shù)千萬(wàn)美元的資金。去年，中國(guó)一顆以古代哲學(xué)家墨子的名字命名的衛(wèi)星，使用量子加密技術(shù)成功實(shí)現(xiàn)了北京與維也納之間的視頻通話。經(jīng)過(guò)四年的規(guī)劃和建設(shè)，北京和上海之間的專用量子通信網(wǎng)絡(luò)也于去年投入使用。

For now, quantum encryption works only over a limited distance. The satellite link between Beijing and Vienna stretched this limit to a record 4,630 miles. On the ground, using optical fiber lines, the ceiling is about 150 miles.

目前，量子加密只能在有限的距離內(nèi)工作。北京和維也納之間的衛(wèi)星連接將這個(gè)距離擴(kuò)大到了創(chuàng)紀(jì)錄的4630英里(約合7451公里)。在地面上，使用光纖線路的最大距離大約是150英里(約合240公里)。

Among China’s investments in quantum encryption, the Micius satellite has received the most attention. The University of Science and Technology of China, the government-backed university that helped launch Micius, led the construction of the ground network, which spans about 1,200 miles — perhaps a hint of aspirations for drastic improvement.

在中國(guó)對(duì)量子加密技術(shù)的投資中，“墨子號(hào)”衛(wèi)星受到的關(guān)注最多。政府出錢支持的中國(guó)科學(xué)技術(shù)大學(xué)幫助發(fā)射了“墨子號(hào)”衛(wèi)星，科大也在牽頭建設(shè)總長(zhǎng)約1200英里(約合1930公里)的量子通信地面網(wǎng)絡(luò)。

The governments of Anhui and Shandong Provinces, through which the fiber-optic network passes, together invested $80 million in the project. Like all major infrastructure projects in China, the plans have had high-level support from the Chinese government.

光纖網(wǎng)絡(luò)途經(jīng)的安徽省和山東省政府總共為項(xiàng)目投資了8000萬(wàn)美元。與中國(guó)所有的重大基礎(chǔ)設(shè)施項(xiàng)目一樣，量子通信項(xiàng)目也得到了中國(guó)政府高層的支持。

This main line is being extended to other cities and regions. The goal by 2030 is a Chinese-built network for sharing quantum encryption keys across the globe.

這條干線正在延伸到其他城市和地區(qū)。中國(guó)的目標(biāo)是，在2030年前，建成一個(gè)連接全球各地的分享量子加密密鑰的網(wǎng)絡(luò)。

Some security experts question the effectiveness of quantum encryption. Because it is so new, it has not been put through anywhere close to the rigorous testing that would give it a stamp of approval from skeptical cryptographers.

一些安全專家對(duì)量子加密的有效性有懷疑。因?yàn)檫@種技術(shù)如此之新，它還沒(méi)有經(jīng)受過(guò)任何可以讓持懷疑態(tài)度的密碼學(xué)家對(duì)技術(shù)表示認(rèn)可的嚴(yán)格測(cè)試。

But Chao-Yang Lu, a professor of physics at the University of Science and Technology of China, said the Beijing-Shanghai quantum network was a significant upgrade.

但科大物理系教授陸朝陽(yáng)說(shuō)，量子通信京滬干線是一次重大的升級(jí)。

With communications sent by traditional means, eavesdroppers can intercept the data stream at every point along a fiber-optic line. A government could tap that line just about anywhere. Quantum encryption cut the number of vulnerable spots in the Beijing-Shanghai line to just a few dozen across 1,200 miles, Professor Lu said.

使用傳統(tǒng)通信方式時(shí)，竊聽(tīng)者可以在光纖線路上的每個(gè)點(diǎn)攔截?cái)?shù)據(jù)流。政府可以在通信線路的任何地方進(jìn)行竊聽(tīng)。陸朝陽(yáng)說(shuō)，量子加密技術(shù)讓長(zhǎng)達(dá)1200英里的京滬干線上易受攻擊的點(diǎn)減少到了幾十個(gè)。

“We admit that it’s an intermediate solution,” he said. “It’s not the final solution. But it’s already a huge improvement in terms of security.”

“我們承認(rèn)這是一個(gè)中間階段的解決方案，”他說(shuō)。“這不是最終的解決方案。但就安全而言，這已經(jīng)是一個(gè)巨大的進(jìn)步。”

In the United States, the government and industry have viewed quantum encryption as little more than a science experiment. Instead, researchers have focused on using ordinary mathematics to build new forms of encryption that can stand up to a quantum computer. This technology would not require new infrastructure.

在美國(guó)，政府和業(yè)界認(rèn)為量子加密不過(guò)是一項(xiàng)科學(xué)實(shí)驗(yàn)。所以，研究人員的精力一直集中在使用現(xiàn)有的數(shù)學(xué)來(lái)構(gòu)建新的、可對(duì)抗量子計(jì)算機(jī)的加密方法。這種做法不需要新的基礎(chǔ)設(shè)施。

But now, spurred by activity in China and recent advances in quantum research, some in the United States are playing catch-up.

但現(xiàn)在，在中國(guó)的做法和最近的量子研究取得進(jìn)展的推動(dòng)下，美國(guó)有些人正在努力追趕。

Qubitekk, a Southern California start-up, is working to secure power grids in Tennessee using the technology. A second start-up, Quantum Xchange, is building a quantum encryption network in the Northeast, hoping to serve Wall Street banks and other businesses. Researchers at Stony Brook University on Long Island are preparing a third venture.

南加州初創(chuàng)企業(yè)Qubitekk正在使用量子加密技術(shù)來(lái)保護(hù)田納西州的電網(wǎng)。另一家初創(chuàng)公司Quantum Xchange正在美國(guó)東北部建設(shè)一個(gè)量子加密網(wǎng)絡(luò)，希望為華爾街銀行和其他企業(yè)提供服務(wù)。位于長(zhǎng)島的石溪大學(xué)(Stony Brook University)的研究人員正在準(zhǔn)備成立另一家企業(yè)。

Small start-ups like Qubitekk are unlikely to match the millions of dollars in infrastructure already created in China for quantum encryption. But many experts believe the more important work will happen in research labs, and the Department of Energy is funding a test network in Chicago that could eclipse the kind of systems deployed in China.

像Qubitekk這樣的小型初創(chuàng)企業(yè)不太可能像中國(guó)為量子加密建立基礎(chǔ)設(shè)施那樣，投入數(shù)百萬(wàn)美元。但許多專家認(rèn)為，更重要的工作將發(fā)生在研究實(shí)驗(yàn)室，美國(guó)能源部正在為芝加哥的一個(gè)測(cè)試網(wǎng)絡(luò)提供資金，該網(wǎng)絡(luò)可能會(huì)讓中國(guó)使用的系統(tǒng)相形見(jiàn)絀。

The Los Alamos and Oak Ridge National Laboratories are working with Qubitekk to secure power grids with quantum technology, and Quantum Xchange is moving equipment into 60 Hudson Street, the old Western Union telegraph hub, which now serves as an internet hub for Lower Manhattan.

洛斯阿拉莫斯國(guó)家實(shí)驗(yàn)室(Los Alamos National laboratory)和橡樹(shù)嶺國(guó)家實(shí)驗(yàn)室都在與Qubitekk合作，使用量子技術(shù)保護(hù)電網(wǎng)。Quantum Xchange正在把設(shè)備搬到哈德遜街60號(hào)，原西聯(lián)(Western Union)電報(bào)中心所在地，現(xiàn)在是曼哈頓下城的一個(gè)互聯(lián)網(wǎng)中心。

Quantum Xchange is building a quantum encryption link between Manhattan and Newark, with plans to connect big banks operating in the two cities. Eventually, it hopes to extend this network up and down the East Coast.

Quantum Xchange正在曼哈頓和紐瓦克之間建設(shè)量子加密連接，并計(jì)劃把在這兩個(gè)城市運(yùn)營(yíng)的大型銀行連接起來(lái)。公司最終的希望是把這個(gè)量子加密網(wǎng)絡(luò)延伸到整個(gè)東海岸。

At places like the University of Chicago, researchers hope to go a step further, exploring what are called quantum repeaters — devices that could extend the range of quantum encryption.

在像芝加哥大學(xué)這樣的地方，研究人員希望再上一層樓，他們正在探索所謂的量子中繼器，即能夠延伸量子加密距離的設(shè)備。

“We’re not there yet,” said David Awschalom, a professor at the University of Chicago who oversees much of the university’s quantum research. “But I am confident this will happen in the next couple of years.”

“我們還沒(méi)有做成，”芝加哥大學(xué)(University of Chicago)教授戴維·奧沙洛姆(David Awschalom)說(shuō)。“但我相信，這將在未來(lái)幾年發(fā)生。”

Quantum communication techniques require new hardware. This includes vast networks of fiber lines — and perhaps satellites — as well as specialized devices capable of detecting individual photons of light.

量子通信技術(shù)需要新的硬件，包括龐大的光纖網(wǎng)絡(luò)——或許還有衛(wèi)星——以及能夠探測(cè)單個(gè)光子的專門設(shè)備。

As Qubitekk worked on quantum encryption networks, it could not obtain the special light detectors it needed to do the work. The start-up originally bought detectors from a small manufacturer in New Jersey, Princeton Lightwave. But in April, this lone American manufacturer handed the detector business over to a company in China, RMY, and Qubitekk’s supply line ran dry.

隨著Qubitekk建設(shè)量子加密網(wǎng)絡(luò)工作的進(jìn)展，公司發(fā)現(xiàn)無(wú)法獲得完成這項(xiàng)工作所需的特殊光子探測(cè)器。這家初創(chuàng)公司最初是從新澤西州的一家叫普林斯頓光波(Princeton Lightwave)的小型制造商那里購(gòu)買了這種儀器。但今年4月，這家美國(guó)制造商將光子探測(cè)器的業(yè)務(wù)轉(zhuǎn)給了一家中國(guó)公司RMY，Qubitekk的供應(yīng)鏈斷了。

RMY has promised hardware to Qubitekk but recently told it that, because of production issues, additional detectors won’t be available until March.

RMY已經(jīng)承諾向Qubitekk提供硬件，但最近通知它，由于生產(chǎn)問(wèn)題，下一批探測(cè)器只能在明年3月后交貨。

Small companies in Europe are selling somewhat similar detectors, and labs across the globe are developing a more advanced type of hardware. But for now, supplies, particularly in the United States, are slim.

歐洲的一些小公司也銷售類似的探測(cè)器，而且全球各地的實(shí)驗(yàn)室正在開(kāi)發(fā)一種更先進(jìn)的儀器。但就目前而言，這種探測(cè)器的供應(yīng)很有限，尤其是在美國(guó)。