I have not proved that the universe is, in fact, a digital computer and that it's capable of performing universal computation, but it's plausible that it is.

[With quantum computers] you can calculate how many bits are in the universe, how much energy it takes to flip them, how much energy exists, and use that to rule out lots of things about the universe's history. Anything that takes more bit flips couldn't have happened.

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.

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.

We couldn't build quantum computers unless the universe were quantum and computing. We can build such machines because the universe is storing and processing information in the quantum realm. When we build quantum computers, we're hijacking that underlying computation in order to make it do things we want: little and/or/not calculations. We're hacking into the universe.

The primary consequence of the computational nature of the universe is that the universe naturally generates complex systems, such as life. Although the basic laws of physics are comparatively simple in form, they give rise, because they are computationally universal, to systems of enormous complexity.

By separating the function of adaptation from the function of maintaining the integrity of individual genes, sex allows much greater diversity while still keeping genes whole. Sex is not only fun, it is good engineering practice.