When you zap things with light to build quantum computers, you're hacking existing systems. You're hijacking the computation that's already happening in the universe, just like a hacker takes over someone else's computer.

Indeed, as the above calculation indicates, to take full advantage of the memory space available, the ultimate laptop must turn all its matter into energy.

The amount of information that can be stored by the ultimate laptop, 10 to the 31st bits, is much higher than the 10 to the 10th bits stored on current laptops.

Bits of ignorance are like viruses that are copied and spread by interaction.

Nothing in life is certain except death, taxes and the second law of thermodynamics. All three are processes in which useful or accessible forms of some quantity, such as energy or money, are transformed into useless, inaccessible forms of the same quantity. That is not to say that these three processes don't have fringe benefits: taxes pay for roads and schools; the second law of thermodynamics drives cars, computers and metabolism; and death, at the very least, opens up tenured faculty positions.

Another feature that everybody notices about the universe is that it's complex.

Thinking of the universe as a computer is controversial.