Towards a demystification of Quantum Mechanics

episode 1: the concept of state

Quantum mechanics is often taught as a “revolution”, leveraging on its paradoxical aspects. Partly, this is due to the fact that teachers tend to mimic the historical development of the theory (that is not always a good idea); partly to the wrong assumption that they make it more interesting. The result is that most people (including professionals) do not really trust it and many consider it impossible to understand (often misquoting prof. Feynman). In fact, quantum mechanics is not so different from classical mechanics, provided you consider the latter as it really is. In this and the following posts I will try to convince you that in fact classical mechanics is much more close to quantum mechanics than you believe.

The first step is to re-examine classical mechanics in view of an introduction to quantum mechanics. This episode is devoted to clarifying the concept of “state”. In the following episodes we will deal with other, often neglected, concepts in classical physics.

Figure taken from Wikimedia made by Geek3

The concept of state

In classical physics we sometimes use the concept of “state”. In particular, in most textbooks you can find that:

1. the state of a pointlike particle is often said to be given when its position and velocity…