Imagine there's a box. Inside the box there is a radioactive source, a detector that records the presence of radioactive particles, a glass bottle containing a poison such a cyanide, and a live cat. The apparatus in the box is arranged so that the detector is switched on for just long enough so that there is a fifty-fifty chance that one of the atoms in the radioactive material will decay and that the detector will record a particle. If the detector does record such an event, then the glass container is crushed and the cat dies; if not, the cat lives. We have no way of knowing the outcome of this experiment until we open the box to look inside; radioactive decay occurs entirely by chance and is unpredictable except in a statistical sense. Actually, there are two possibilities - either the cat is dead, or alive. In common sense. But according to the quantum physics there are no possibilities - only a superposition of them, which is being divided into two worlds when an observer looks into the box. It can be said that there is the superposition of two worlds and at the moment of looking at the cat the observer creates reality, or what we call reality. Although it seems strange and spooky, the quantum physics is based on it. Our everyday decisions are creating a tree of ghostly worlds.
Everyone who is not confused after reading this extract should know that he or she did not understand the semi-philosophical sense of the quantum physics. And it is sometimes very good to understand it, mainly when we talk about the atom bomb, lasers, the microchip and the DNA - because all of the greatest technical achievements of the 20th century are based on quantum level. The thing that divides the world into quantum and classical ones is Planck's constant, the constant which makes bigger objects uncountable in terms of quantum level. That's why we can speak about still classical physics when we think about the surroundings. There is a question - is the perception of the world as the Great Machine steered by the Creator, where we have no choice of what we are going to do still reasonable when the law of determinism is replaced by the law of probability and chance from tiny particles to huge Universe? The split between Einstein and Newton is well described in the book.