Exponential Growth

Kevin Kelly has a very interesting and very extensive discussion of Moore's Law and a number of other laws of technical growth. He was an editor for Wired magazine and is a prolific author. My favourite book by him is Out of Control.

Here are some key bits from Kevin Kelly's article "Was Moore's Law Inevitable":

Secondly, even a cursory glance reveals the astounding regularity of Moore's line. From the earliest points its progress has been eerily mechanical. Without interruption for 50 years, chips improve exponentially at the same speed of acceleration, neither more nor less. It could not be more straight if it had been engineered by a technological tyrant. Yet, we are to believe that this strict nonwavering trajectory came about via the chaos of the global marketplace and uncoordinated ruthless scientific competition. The line is so straight and unambiguous that it seems curious anyone would need convincing by Moore and Mead to "believe" in it. The question of faith lies in whether one believes the force of this "law" lies within the technology itself, or in a self-fulfilling social prophecy. Is Moore's law inevitable, a direction pushed forward by the nature of matter and computation, and independent of the society it was born into, or is it an artifact of self-organized scientific and economic ambition?

In any case, at some point on our planet, or any planet, the curve will plateau out. Moore's law will not continue forever. Any specific exponential growth will inevitably smooth out into a typical S-shaped curve. This is the archetypical pattern of growth: after a slow ramp up, gains takeoff straight up like a rocket, and then after a long run level out slowly. Back in 1830 only 37 kilometers of railroad track had been laid in the US. That count doubled in the next ten years, and then doubled in the decade after that, and kept doubling every decade for 60 years. In 1890 any reasonable railroad buff would have predicted that the US would have hundreds of millions of kilometers of railroad by a hundred years later. There would be railroad to everyone's house. Instead there were fewer than 400,000 kilometers. However, Americans did not cease to be mobile. We merely shifted our mobility and transportation to other species of invention. We built automobile highways, and airports. The miles we travel keep expanding, but the exponential growth of that particular technology peaked and plateau.

Much of the churn in the technium is due to our tendency to shift what we care about. Mastering one technology engenders new technological desires. A recent example: The first digital cameras had very rough picture resolution. Then scientists began cramming more and more pixels onto one sensor to increase photo quality. Before they knew it, the number of pixels possible per array was on an exponential curve, heading into megapixel territory and beyond. But after a decade of acceleration, consumers shrugged off the increasing number of pixels; the current resolution was sufficient. Their concern shifted to the speed of the pixel sensors, or the response in low light -- things no one cared about before. So a new metric is born, and a new curve started, and the exponential curve of ever-more pixels per array will gradually abate.

Moore's Law is headed to a similar fate. When, no one knows. "Moore's Law, which has held as the benchmark for IC scaling for more than 40 years, will cease to drive semiconductor manufacturing after 2014," Len Jelinek, the director of a major semiconductor manufacturer, claimed in 2009. Carl Anderson, an IBM Fellow, announced at an industry conference in April, 2009 that the end of Moore's Law was at hand: "There was exponential growth in the railroad industry in the 1800s; there was exponential growth in the automobile industry in the 1930s and 1940s; and there was exponential growth in the performance of aircraft until they reached the speed of sound. But eventually exponential growth always comes to an end." But IBM has been wrong several times before. In 1978, IBM scientists predicted Moore's Law had only 10 years left. Whoops. In 1988, they again said it would end in 10 years. Ooops, again. Gordon Moore himself predicted his law would end when it reach 250 nanometer manufacturing, which it passed in 1997. Today the industry is aiming for 20 nanometers. In 2009, Intel CEO Craig Barrett said "We can scale it down another 10 to 15 years. Nothing touches the economics of it."

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I suspect Moore's Law is something we don't have much sway over, other than its doubling period. Moore's Law is the Moira of our age. In Greek mythology the Moira were the three Fates. Usually depicted as dour spinsters, one Moira spun the thread of a newborn's life. The other Moira counted out the thread's length. And the third Moira cut the thread at death. A person's beginning and end were predetermined. But what happened in between was not inevitable. Humans and gods could work within the confines of one's ultimate destiny.

Go read the whole article. It is absolutely fascinating!