p.3 The universe is a quantum computer.
This begs the question: What does the universe compute? It computes itself. The universe computes
its own behavior. As soon as the universe began, it began computing. [JLJ - This sounds a lot like an answer to a test question
where you don't really know the answer, but you are trying to BS the teacher. Seth, if the universe is a quantum computer,
where did it come from? Who made it? What happened before the universe began? Did the quantum computing universe malfunction
when you wrote that, or did it malfunction when it made you, or did it malfunction when I criticized what you wrote? These
are tough questions, Seth.]
p.4 In school, I learned that the physical laws governing the universe are surprisingly simple. How could
it be, I wondered, that the intricacy and complexity I saw outside my bedroom window was the result of these simple physical
laws? I decided to study this question and spent years learning about the laws of nature.
p.129 Let's look more closely at atom zapping, a process that allows us to talk to atoms, and to hear them
talk back. [JLJ - I wonder if you can join the "friends and family plan"]
p.176 The primary consequence of the computational nature of the universe is that the universe naturally
generates complex systems, such as life.
p.183 Ray Solomonoff originally defined algorithmic information while looking
for a formal mathematical theory of Occam's razor. The medieval philosopher William of Occam was interested in finding the
simplest explanation for observed phenomena. Pluralitas non est ponenda sine necessitate, he declared; "plurality
should not be posited without necessity." Occam urged us to accept simple explanations for phenomena over complex ones...
Occam's razor cuts away complex explanations by declaring simple ones to be a priori more plausible. [JLJ - corrected typo
in Latin phrase - let's not complicate things unnecessarily.]
p.186 Quantum fluctuations are the monkeys that program the universe. [JLJ - I could explain this,
but just quoting it and leaving it unexplained is more fun]
p.186-187 Halfway through my Ph.D in physics at Rockefeller University, I was almost expelled...
Most of the other graduate students were working on string theory... I couldn't for the life of me see why what I was doing
was crazier than string theory.
p.193 "Effective complexity," a measure of the amount of regularity in a
system... is a simple and elegant measure of complexity... The amount of information required to describe a system's regularities
is its effective complexity.
p.194 How can we engineer complex systems that are still robust in their behavior? ...Keep It Simple, Stupid!
p.194 One promising technique for engineering complex systems is known as axiomatic design, an approach
conceived by Nam Suh, the former head of MIT's Department of Mechanical Engineering. The idea of axiomatic design
is to minimize the information content of the engineered system while maintaining its ability to carry out its functional
requirements. Properly applied, axiomatic design results in airplanes, software, and toasters all just complex enough,
and no more, to attain their design goals. Axiomatic design minimizes the effective complexity of the engineered system while
maintaining the system's effectiveness. Keep It Simple, Stupid - but not too simple.
p.209 After the Big Bang, as different pieces of the universe tried out all possible ways of processing
information, sooner or later, seeded by quantum accident, some piece of the universe managed to find an algorithm to reproduce
itself. That accident led to life. Life evolved by processing genetic information to try out new strategies for survival and
reproduction. After trying out billions of strategies, some living systems eventually discovered sex, a technique that vastly
increases the rate at which new evolutionary strategies and algorithms can be explored, because it speeds up the rate of genetic
information processing. After billions of years of sex, living creatures had evolved all sorts of methods for getting and
processing information - eyes, ears, and brains, to name a few... It is the richness and complexity of our shared information
processing that has brought us this far. The invention of human language, coupled with diverse social development, was
a true information-processing revolution that has substantially changed the face of the Earth.
p.211 Some of the information processing the universe performs is indeed thought - human thought. Some of
that information processing, like digital computation, can resemble thought.
p.214 Gell-Mann... does not hesitate to let you know if your own speculations on the subject are mistaken.
At one point in our three-hour discussion I hazarded an opinion about an aspect of quantum mechanics with which I was not
sufficiently familiar. "No," said Gell-Mann, his voice getting louder. "No!" Putting his forehead down on the table
where we were sitting, he began pounding the table with his fists. "No! No! No! No!! No!!" Here, I thought, was someone
I could work with.
