As previously mentioned in part 1 of this blog post, Moore’s law is not a physical law of science. Rather it may be considered a trend or a general rule. This begs the following question. How Long Will Moore’s Law Hold?

There are numerous estimates regarding how long Moore’s law will hold. Since it is not a physical law, its applicability is routinely questioned. For approximately the last half century, each estimate, at various points in time, has predicted that Moore’s law would hold for another decade. This has been occurring for almost five decades.

In 2005 Gordon Moore stated in an interview that Moore’s law “can’t continue forever. The nature of exponentials is that you push them out and eventually disaster happens.” Moore noted that transistors eventually would reach the limits of miniaturization at atomic levels. “In terms of size [of transistors] you can see that we’re approaching the size of atoms, which is a fundamental barrier, but it’ll be two or three generations before we get that far—but that’s as far out as we’ve ever been able to see. We have another 10 to 20 years before we reach a fundamental limit.”

However, new technologies are emerging to use molecules individually positioned, replacing transistors altogether. This means computer “switches” will not be transistors but molecules. The position of the molecules will be the new switches. This technology is predicted to emerge by 2020 (Baptiste Waldner, Nanocomputers and Swarm Intelligence, 2008).

Some see Moore’s law extending far into the future. Lawrence Krauss and Glenn D. Starkman predicted an ultimate limit of around six hundred years (Lawrence M. Krauss, Glenn D. Starkman, “Universal Limits of Computation,” arXiv:astro-ph/0404510, May 10, 2004).

I worked in the semiconductor industry for more than thirty years, during which time Moore’s law always appeared as if it would reach an impenetrable barrier. This, however, did not happen. New technologies constantly seemed to provide a stay of execution. We know that at some point the trend may change, but no one really has made a definitive case as to when this trend will end. The difficulty in predicting the end has to do with how one interprets Moore’s law. If one takes Moore’s original interpretation, which defined the trend in terms of the number of transistors that could be put on an integrated circuit, the end point may be somewhere around 2018 to 2020. Defining it in terms of “data density of an integrated circuit,” however, as we did regarding AI, removes the constraint of transistors and opens up a new array of technologies, including molecular positioning.

Will Moore’s law hold for another decade or another six hundred years? No one really knows the answer. Most people believe that eventually the trend will end, but when and why remain unanswered questions. If it does end, and Moore’s law no longer applies, another question emerges.

What Will Replace Moore’s Law?

Ray Kurzweil views Moore’s law in much the same way we defined it, not tied to specific technologies but rather as a “paradigm to forecast accelerating price-performance ratios.” From Kurzweil’s viewpoint:

 Moore’s law of Integrated Circuits was not the first, but the fifth paradigm to forecast accelerating price-performance ratios. Computing devices have been consistently multiplying in power (per unit of time) from the mechanical calculating devices used in the 1890 U.S. Census, to [Newman’s] relay-based “[Heath] Robinson” machine that cracked the Lorenz cipher, to the CBS vacuum tube computer that predicted the election of Eisenhower, to the transistor-based machines used in the first space launches, to the integrated circuit-based personal computer. (Raymond Kurzweil, “The Law of Accelerating Returns,”

In the wider sense, Moore’s law is not about transistors or specific technologies. In my opinion it is a paradigm related to humankind’s creativity. The new computers following Moore’s law may be based on some new type of technology (e.g., optical computers, quantum computers, DNA computing) that bears little to no resemblance to current integrated-circuit technology. It appears that what Moore really uncovered was humankind’s ability to cost-effectively accelerate technology performance.

Source: The Artificial Intelligence Revolution (2014), Louis A. Del Monte