23. Applications of quantum mechanics – life, pleasure and their means
Now that we can look at quantum effects without ideological baggage, let us have some ser-
ious fun in the world of quantum theory. The quantum of action has important consequences
for biology, chemistry, technology and science fiction. We will only explore a cross section
of these topics, but it will be worth it.
A special form of electromagnetic motion is of importance to humans: life. We mentioned
at the start of quantum theory that life cannot be described by classical physics. Life is a
quantum effect. Let us see why.
Living beings can be described as objects showing metabolism, information processing,
information exchange, reproduction and motion. Obviously, all these properties follow from
a single one, to which the others are enabling means:
Living beings are objects able to reproduce.∗
This definition implies several consequences. In order to reproduce, living beings must be
able to move in self-directed ways. An object able to perform self-directed motion is called
a machine. All self-reproducing beings are machines.
Since reproduction is simpler the smaller the system is, most living beings are extremely
small machines for the tasks they perform, especially when compared to human made ma-
chines. This is the case even though the design of human machines has considerably fewer
requirements: human-built machines do not need to be able to reproduce; as a result, they
do not need to be made of a single piece of matter, as all living beings have to. But despite
all the restrictions nature has to live with, living beings hold many miniaturization world
The brain has the highest processing power per volume of any calculating device so far.
Just look at the size of chess champion Gary Kasparov and the size of the computer against
which he played.
The brain has the densest and fastest memory of any device so far. The set of compact
disks (CDs) or digital versatile disks (DVDs) that compare with the brain is many thousa