Microsoft Word Kurzweil, Ray The Singularity Is Near doc

Exponential Trends Don't Last Forever.
The classical metaphorical example of exponential trends hitting a wall is 
known as "rabbits in Australia." A species happening upon a hospitable new habitat will expand its numbers 
exponentially until its growth hits the limits of the ability of that environment to support it. Approaching this limit to 
exponential growth may even cause an overall reduction in numbers—for example, humans noticing a spreading pest 

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may seek to eradicate it. Another common example is a microbe that may grow exponentially in an animal body until a 
limit is reached: the ability of that body to support it, the response of its immune system, or the death of the host. 
Even the human population is now approaching a limit. Families in the more developed nations have mastered 
means of birth control and have set relatively high standards for the resources they wish to provide their children. As a 
result population expansion in the developed world has largely stopped. Meanwhile people in some (but not all) 
underdeveloped countries have continued to seek large families as a means of social security, hoping that at least one 
child will survive long enough to support them in old age. However, with the law of accelerating returns providing 
more widespread economic gains, the overall growth in human population is slowing. 
So isn't there a comparable limit to the exponential trends that we are witnessing for information technologies? 
The answer is yes, but not before the profound transformations described throughout this book take place. As I 
discussed in chapter 3, the amount of matter and energy required to compute or transmit one bit is vanishingly small. 
By using reversible logic gates, the input of energy is required only to transmit results and to correct errors. Otherwise, 
the heat released from each computation is immediately recycled to fuel the next computation. 
As I discussed in chapter 5, nanotechnology-based designs for virtually all applications—computation, 
communication, manufacturing, and transportation—will require substantially less energy than they do today. 
Nanotechnology will also facilitate capturing renewable energy sources such as sunlight. We could meet all of our 
projected energy needs of thirty trillion watts in 2030 with solar power if we captured only 0.03 percent (three ten-
thousandths) of the sun's energy as it hit the Earth. This will be feasible with extremely inexpensive, lightweight, and 
efficient nanoengineered solar panels together with nano-fuel cells to store and distribute the captured energy.