Chapter 1: Basic Principles

We start from the following five basic principles to construct all other physical laws and equations. These five basic principles are: (1) Constituent principle: the basic constituents of matter are various kinds of identical particles. This can also be called locality principle; (2) Causality principle: the future state depends only on the present state; (3) Covariance principle: the physics should be invariant under an arbitrary coordinate transformation; (4) Invariance or Symmetry principle: the spacetime is homogeneous; (5) Equi-probability principle: all the states in an isolated system are expected to be occupied with equal probability. These five basic principles can be considered as physical common senses. It is very natural to have these basic principles. More important is that these five basic principles are consistent with one another. From these five principles, we derive a vast set of equations which explains or promise to explain all the phenomena of the physical world.