When you visit a doctor in a few years, you can expect to be accompanied by a virtual version of yourself. This so-called digital twin will be a working model of your body that can be called up on a doctor's computer screen. Updated with your latest vital signs, it will help the doctor make an accurate diagnosis. It also opens the door to medications and procedures designed specifically for you, significantly increasing recovery rates.
This may seem like a fantasy, but the foundation is being laid. Researchers at Queen Mary University of London are already using computer simulations of individual patients' hearts to evaluate different treatments for atrial fibrillation, a common condition. It would be far too risky to experiment with someone's real heart in this way. Since scientists are also working on other bodies, it seems likely that they will eventually connect to form a virtual body.
As our Science and Technology section reports, digital twins are starting to pop up everywhere. Among other things, they monitor the health of airplane jet engines, monitor Uber's vehicle network, and replicate Amazon's extensive supply chain well enough that the online retailer can accurately predict sales several years from now. They help local authorities respond to the consequences of flooding and allow car manufacturers to save years on the development of new models by simulating test drives and crashes. Twins are also being developed to help manage factories, companies and entire cities. All of this is being accelerated by recent advances in artificial intelligence (AI), giving twins the ability to make predictions about their physical counterparts, and fine-tune themselves based on new data.
Digital twins started out as basic computer models of physical objects and systems. As computers have become more powerful, twins have become more sophisticated. Complex design and modeling software means that many physical objects initially take shape in the virtual world. Tiny sensors, which can measure all kinds of things, feed twins with real-time data and ensure they mirror their physical counterparts. For example, a Formula 1 racing car may have more than 250 sensors that update its digital twin during a Grand Prix.
The use of AI goes much further, allowing virtual models to become more sophisticated and real-world activities to be simulated and optimized. You might worry that this portends a dystopian future; Morpheus, a character from a 1999 science fiction film in which a sentient machine subjugates humanity through a pervasive virtual reality, had a name for it. As he said: “The Matrix is everywhere. It's all around us.”
The reality is more prosaic. The idea of creating symbolic representations of things in the real world is ancient. Many ancient civilizations built architectural models, sometimes to place in tombs, but also to figure out how to build things. Double-entry bookkeeping, developed in the 15th century, was a paper record of a merchant's finances. The Phillips Machine, a hydraulic computer from the 1940s, created a physical “twin” of national economic flows. Spreadsheets and supply chain management systems allow companies to record transactions, track inventories, make forecasts and model future scenarios.
Today's digital twins extend this process, making it easier for people to tackle complex problems. They can act as virtual crystal balls, allowing people to see into the future, spot problems before they become reality, and test wild ideas without real-world consequences. For companies, this should mean better designs, more streamlined operations and fewer costly blunders. For society, the promise is just as tempting: personalized healthcare, cities that flow and breathe more easily and, thanks to the threats revealed by climate models, clues about how the planet might avoid environmental disaster. Digital Twins provide the ultimate sandbox where castles can be built and tested before they become reality.
Could these virtual doppelgängers go rogue? That could happen if they are poorly programmed or hacked. Preventable medical conditions can be ignored, business systems can go haywire, and critical power plants can be compromised. Digital twins will gobble up mountains of data, some of it wrong, some of it biased, and much of it raising privacy and surveillance concerns. There's also the danger of tunnel vision, as people increasingly rely on digital twins – and miss things that sensors may not be able to capture. Yet these risks are not specific to digital twins. They apply to all emerging technologies, as they always have been and always will be. Such concerns should be taken into consideration, as they are in the current debate over the use of AI. The rise of the digital mirror world will undoubtedly raise new questions, but its potential benefits are already clearly visible.
© 2024, The Economist Newspaper Limited. All rights reserved. From The Economist, published under license. Original content can be found at www.economist.com
