Introduction
Classical mechanics is the oldest and most commonly encountered branch of physics. It studies the motion of every-day objects and describes the majority of phenomena which we observe.
Assumptions of Classical Mechanics
As with any physics model, classical mechanics is a simplification of the real world which makes certain assumptions in order to function. Whilst we have no way of deriving these assumptions, experimental observations indicate that they are correct or at least are good enough approximations for correctly describing most situations.
Space and Time
Classical mechanics models space and time as a topological space which is homeomorphic to the Euclidean Space and which has certain properties. This means that one always needs four numbers to describe the location of an object. These numbers are known as the coordinates of the object and there are two kinds of them. Three of the numbers are spatial coordinates and one number is a temporal coordinate.
Symmetries
There are also certain symmetries which the world appears to exhibit.
Empirical Law: Space Symmetry
The laws of physics appear to be the same everywhere, at all point of time.
Empirical Law: Time Symmetry
The laws of physics appear to be the same always, at all points of time.