Quantum theory confronts us with bizarre paradoxes which contradict the logic of classical physics. At the subatomic level, one particle seems to know what the others are doing, and according to Heisenberg's "uncertainty principle", there is a limit on how accurately nature can be observed. And yet the theory is amazingly accurate and widely applied, explaining all of chemistry and most of physics. "Introducing Quantum Theory" takes us on a step-by-step tour with the key figures, including Planck, Einstein, Bohr, Heisenberg and Schrodinger. Each contributed at least one crucial concept to the theory. The puzzle of the wave-particle duality is here, along with descriptions of the two questions raised against Bohr's "Copenhagen Interpretation" - the famous "dead and alive cat" and the EPR paradox. Both remain unresolved.
I found this title rather less accessible than
The book deals with the development of quantum theory, the structure and behaviour of matter at the atomic level. It provides a useful description of the key players involved and the interaction as ideas are developed almost like the passing of the baton in a relay. An idea being challenged, added to, discarded or built upon as physicists throughout the 20th century and particularly its first half, struggle to build their understanding of matter. The description follows the various ideas, each of which provided a step along the process of learning, some to be discarded as thinking moved on, others still part of our current understanding.
Though some of the detail, even in this brief primer, may be a little difficult to fathom, at the heart of our understanding of the nature of matter are two key ideas, perhaps two design principles that appear to underpin everything. These ideas are uncertainty and connectedness.
Of course I could just be seeing these ideas, these connections, because they are what I am receptive to. Perhaps this is an example that we see what we want to see, what we are able or prepared to see, and here is another connection. I was intrigued by the description of work on understanding the nature of light, which in some ways behaves as a wave, and in some ways behaves as a particle. The resolution of this paradox is that it becomes either wave like or particle like, depending on how we choose to see it. The observer causes it to exist in that form. As Niels Bohr put it,
“Whether an object behaves as a wave or a particle depends on your choice of apparatus for looking at it”
As for connectedness, some of the mathematics suggests the idea of non-locality, that all matter is connected. Interaction does not diminish with distance and acts simultaneously without crossing space. Matter on one side of the universe, knows all about matter on the other side of the universe and they act together.
The validity and consequences of this amazing idea are still being explored, but it raises fascinating questions about our concepts of connectedness, and our apparent preference to dissect our world and avoid the realities of a jagged edged world of chaos.
This is an interesting little book, the ideas of which compliment those in Introducing Chaos and Introducing Fractal Geometry, but may perhaps be the least immediately relevant of the three for those seeking to extend their thinking.