Sometimes it feels like we are right at the doorway to the future. With all the extremely brilliant people working on problems like self-driving cars, understanding the human genome, building AI drones and inventing alternative energy sources, it seems that it should just be a matter of time before we slowly but surely ascend to a post-scarcity transhumanist techno-utopia. Many of us at Stanford have never experienced a single period of stagnation in our lives when it comes to the progressive march of modern conveniences. Technology has always gotten better and with each passing year a mundane and boring part of our routine is made easier and lazier with technology.
Remember the days before Amazon Prime, smartphones, Facebook and Google Maps? That was just 10 years ago. That is not even a single generation. In such a brief period of time, we saw entire economies grow from nothing and entire sets of social norms created and thrown away. Our movies went from VHS to DVD to Blu-ray to Netflix and our computers from desktops to laptops to iPhones. With ubiquitous electronic communication, the world shrunk, our cultures collided and our shared identities fragmented.
For those of us who grew up knowing only technological progress, it is natural to assume that this state of constant change is all that there ever was and will be. After all, technology can only keep getting better and our lives will be even more “delightful” and “convenient” in a future of drone delivery services and automated highways. But this manner of seeing the future rests on the faith that the exponential growth of technology will hold forever, that if we expend enough talent and time on a problem, the solution will keep getting better incrementally. Charts showing lines going upwards at exponential rates dominate our mental model of technological growth.
The reality, however, is more nuanced.
Consider the plane propeller. It was pioneered by the Wright brothers at the turn of the 20th century and by the Second World War, propeller technology had advanced to the point where their spin rates were approaching the limits imposed by the laws of physics. As speeds approach the sound barrier, the efficiency of propeller technology faces an insurmountable barrier. Outside of urban legends, no propeller-driven aircraft has ever come close to breaking the speed of sound, despite 50 years of ceaseless improvement and innovation from Kitty Hawk to the Battle of the Coral Sea. It was only the invention of the jet engine that introduced a paradigm shift and brought us to the age of modern aviation.
There is nothing in the invention of powered flight and propeller technology that guaranteed the subsequent invention of jet engines. And if jet engines were never discovered, then we would have continued to be limited by the physics of propellers. As hard as it may be to see in a moment of change, technology growth is discontinuous. Just as aerodynamics imposes limits on propeller speeds, there are limits to the growth of digital technology today.
The present paradigm we live in is one of semiconductor microcontrollers and the vast global information network enabled by them. As manufacturing techniques improved, microprocessors doubled in speed roughly every two of the last 50 years. This is widely known as Moore’s Law. Many of the enormous changes human societies experienced can be attributed to this growth in computational power: the rise of complex financial instruments, cheap goods produced by a global supply chain, on-demand personal computing, quantification and datafication of every aspect of our lives by tech companies. It took decades of continuous hard work to realize the full potential of silicon semiconductors invented in the 1940s, but ultimately we have really just been making faster propellers and reaping the benefits.
Moore’s Law is limited by the minimum size of a transistor, which in turn is limited by the size of atoms. A 2014 IEEE report concludes that “Moore’s Law is not dead, but it has clearly reached old age, and no fundamental technology has emerged to replace it.” And just as the propeller did not imply the jet engine, quantum computing, widely seen as our best chance beyond Moore’s Law, still remains an uncertainty.
The mentality of constant progress compels us to be optimistic that an easy technological solution for the today’s problems of will always be found tomorrow, but history shows that extrapolation can be troubling. In the ’60s, the sudden tech boom cumulating in moon landing led people to predict the age of human-like artificial intelligence, flying cars and cold fusion. None of those things came to fruition because they face physical limits that require fundamental paradigm shifts and not incremental innovation to overcome and those breakthroughs never happened.
Of course, there will continue to be progress; we are not done making faster propellers just yet. But as we look forward to (or dread the coming of) a future of delivery drones, wearable computers, self-driving cars and human augmentation, we should keep our faith in the power of exponential growth in check. There are underlying limits to every growth paradigm, and if we keep growing at exponential rates we will only hit those limits faster. In the present paradigm, we have gone from Google trying to organize the world’s information to smartphone apps trying to make micro optimizations to our “social” interactions. The low hanging fruits for semiconductor-based growth are gone and the next Google will have to bank on more than Moore’s Law to succeed.
Contact Raven Jiang at jcx ‘at’ stanford.edu.