It already ranks among the biggest investment booms in modern history. This year America's large tech firms will spend nearly $400bn on the infrastructure needed to run artificialintelligence (AI) models. OpenAI and Anthropic, the world's leading modelmakers, are raising billions every few months; their combined valuation is approaching half a trillion dollars. Analysts reckon that by the end of 2028 the sums spent worldwide on data centres will exceed $3trn.

在现代史上，这已经跻身规模最大的投资热潮之列。今年，美国大型科技公司将在运行人工智能（AI）模型所需的基础设施上投入近4000亿美元。全球领先的AI模型开发商OpenAI和Anthropic每隔数月即融资数十亿美元，两家公司总估值接近5000亿美元。分析师预测，到2028年底，全球建设数据中心的总花费将超过3万亿美元。

The scale of these bets is so vast that it is worth asking what will happen at payback time. Even if the technology succeeds, plenty of people will lose their shirts. And if it doesn't, the economic and financial pain will be swift and severe.

这些赌博式的投资规模巨大，真该想想投资的回报如何。即便这项技术成功，仍将有许多投资者血本无归。而倘若该技术失败，经济与金融将会遭受迅速且剧烈的打击。

Investors always flock to promising technologies, but the AI rush is more extreme than many past booms.Boosters say that artificial general intelligence (AGI)—models that are better than the average human at most cognitive tasks--could be only a few years away. The first firm to achieve it could reap unimaginable returns. Investors and innovators know they may not be backing the right model. But if they spend slowly and cautiously, they may as well not bother to spend at all.

投资者总是蜂拥追逐前景广阔的技术，但当前这场AI热潮比以往许多热潮都更为极端。鼓吹者宣称，通用人工智能（AGI）——在大多数认知任务上超越普通人类水平的模型——可能仅需数年便能实现。首家获此技术的公司可能得到难以想象的收益。投资者与创新者深知自己的押注未必正确，但若投资步伐迟缓或过于谨慎，则无异于主动放弃。

Consequently, a relentless investment race is under way, with big tech firms splurging on the computing power needed to build the biggest models.A growing cast of extra players, from property developers to electricity generators, has been drawn in. Oracle is the latest to join the party. Its value surged on September 10th after it published an ambitious forecast for its AI related cloud business, briefly turning its boss,Larry Ellison, into the world's richest man.

因此，一场激烈的投资竞赛如火如荼展开了，为构建最大的模型，大型科技公司在算力上投入重金。从房地产开发商到发电企业，越来越多的行业卷入了这场浪潮。甲骨文公司是最新一例：公司雄心勃勃地公布进军AI云业务后，9月10日，其市值应声暴涨，而其老板拉里·埃里森也一度成为世界首富。

No matter what happens, many investors will lose money. In the rosiest scenario AGI will arrive and usher in a new world of economic growth of perhaps 20% a year. Some shareholders would enjoy astronomical returns; many others would face big losses.

无论结局如何，很多投资者都会面临亏损。最乐观的情形是，AGI顺利落地，从而开创年经济增长率或达20%的新纪元。倘真如此，有些股东将获得天文数字级的收益，而其他许多人则会蒙受巨额亏损。

More mundane scenarios should also be considered, however. The technology may evolve in ways that investors do not expect. When alternating current eventually prevailed in America in the 19th century, for instance, directcurrent electricity firms were overshadowed and forced to consolidate. Today investors reckon that the probable AI winners are those that can run the biggest models. But, early adopters are turning to smaller language models,which could suggest that less computing capacity may be needed after all.

然而，我们亦应考虑那些波澜不惊的情形。技术演进方式可能会出乎投资者的预料，比如，19世纪，交流电在美国最终大行其道时，直流电企业便黯然失色并被迫整合。如今，投资者认为，能够运行最大模型的公司或将成为AI领域的赢家。但是，早期使用者正悄然转向更精简的语言模型，这可能意味着所需的算力也许根本没那么大。

Or the road to widespread adoption could be slower and bumpier than investors expect, giving today's AI laggards a fighting chance. Niggles in the technology, the difficulty of quickly supplying electric power, or managerial inertia could mean that take-up is more gradual than first hoped. As they revise down their expectations for AI revenues,many investors and creditors could become less willing to countenance huge investments. The flow of capital could slow; some startups, struggling under the weight of losses, could fold altogether.

或许，技术普及之路会比投资者预期的更为缓慢曲折，这将给当前AI领域的落后者奋力一搏的机会。技术层面的小故障、电力供应的迟缓或企业的管理不力，都可能使技术跟进的速度不及最初的预期。随着很多投资者和债权人对AI收益预期的逐步下调，他们可能不再那么心甘情愿地投入巨资。资本流动可能放缓.而部分在亏损重压下挣扎的初创企业或将彻底出局。

What would such an AI chill be like?For a start, a lot of today's spending could prove worthless. After its 19thcentury railway mania, Britain was left with track, tunnels and bridges; much of this serves passengers today. Bits and bytes still whizz through the fibre-optic networks built in the dotcom years. The AI boom may leave a less enduring leg.acy. Although the shells of data centres and new power capacity could find other uses, more than half the capex splurge has been on servers and specialised chips that become obsolete in a few years.

AI寒潮何堪想象？首先.目前很多的巨额投入可能会打了水漂。19世纪的铁路狂热过后，英国尚遗留下铁轨，隧道与桥梁等基础设施，其中大部分至今仍在服务客运；互联网热潮时建设的光纤网络，至今仍有数据驰骋其间。而AI热潮留下的遗产或许远没有那么持久。尽管数据中心外部建筑与新扩建的电力设施或可另作他用，但超过一半的资本都投向了数年内即告淘汰的服务器和专用芯片。

The good news is that today's financial system could probably absorb the blow. Some technological busts have been brutal; after Britain's railway bubble burst in the 1860s banks were left with big losses, leading to a credit crunch. So far, however, much of the investment in data centres has been bankrolled from the deep well of bigtech profits.

所幸当今金融体系或许尚能承受这样的冲击。历史上有过残酷的技术泡沫破灭：19世纪60年代，英国铁路泡沫破灭后，银行体系承受巨额亏损，继而引发信贷紧缩。但迄今为止，数据中心建设的大部分资金都源自科技巨头雄厚的利润储备。

Although firms including Meta are turning to debt to help fund their latest investments, their lucrative businesses and robust balance-sheets mean they are well positioned to finance a technological boom. Among the keenest to provide that credit are private-market funds, which are typically funded by rich individuals and institutions rather than ordinary depositors. AI startups tend to be financed by well-capitalised venture and sovereign-wealth funds that could withstand losses.

尽管Meta等公司正通过举债为最新投资计划融资，但其利润丰厚的核心业务与稳健的资产负债表意味着它们完全有能力为技术热潮提供资金。最热衷提供这类信贷的是私募基金，这些资金通常来源于富豪个人或机构而非普通储户。而AI初创企业往往由资金雄厚的风险投资机构及主权财富基金注资，这些机构有能力承受潜在损失。

However, trouble spots could still emerge. The more the investment boom spreads, the more financing structures could get riskier, and the more indebted firms could be drawn in. Power companies are desperate to increase their investments to supply AI with the electricity it needs; a heavily indebted utility could easily become overextended.

然而，风险隐患仍可能悄然出现。投资热潮越是蔓延.融资结构就越有风险，陷入债务的企业也就越多。电力公司正孤注一掷地增加投资以满足AI的电力需求，但对于负债累累的公用事业公司而言，极易被过度扩张拖垮。

America's economy, too, would suffer a nasty shock. By one estimate,the AI boom has contributed 40% of its GDP growth over the past year--a staggering figure for a sector that accounts for just a few per cent of total output.If investment projects are scaled back,or ditched altogether, that will translate into economic pain as fewer data centres are built, and fewer workers are employed to build them.

美国经济亦将遭受重挫。据估算，过去一年AI热潮贡献了其GDP增长的40%—对于仅占经济总量几个百分点的行业而言，这一数字堪称惊人。若投资项目缩减或彻底终止，数据中心建设数量就会减少，相关就业岗位也会萎缩，这一切将直接转化为经济阵痛。

To make matters worse, falls in the stock market could cause asset owners to cut back on their spending. Because the valuations of AI-related companies have rocketed, portfolios today are dominated by a handful of tech firms.And households are more exposed to stocks than they were in 2000; if prices fall, their confidence and spending could take a knock. The poorest would be spared, because they tend to hold few stocks. But it is the rich who have fuelled consumption in America over the past year. Robbed of its sources of strength, the economy would weaken as tariffs and high interest rates take a toll.

更令人担忧的是，股市下跌可能引发资产所有者紧缩开支。由于AI相关企业的估值已飙升，现今的投资组合均由少数科技巨头所主导。而且.与2000年相比，美国家庭更易受股市影响，一旦股价下跌，民众信心与消费能力将遭受双重打击。因持股较少，最贫困人群或能幸免。但是，过去一年推动美国消费的核心力量恰恰是富裕阶层。若失去这关键动力，加之关税与高利率持续施压，美国经济必将疲弱。

The bigger the boom gets, the bigger the knock-on consequences of an AI chill could be. If the technology ends up fulfilling the extravagant promises that have been made for it, a new chapter of history will open. However, the story of its frenzied pursuit will make the textbooks, too.

这场AI热潮声势愈浩大，其降温引发的连锁冲击便可能愈深远。若技术最终能兑现人们对其寄予的远大期许，历史将开启新篇。无论怎样，这场狂热追捧也都可以编入教科书，予人警示和启迪。