Relativity
Please Note: This is my own, rather poor attempt at a derivation of some of the important principles of Relativity. In this discussion I intend to keep the mathematics as simple as possible.
The study of Relativity can be split into two major sections:
 Special Relativity  which considers the properties of space and time in uniformly moving frames of reference.
 General Relativity  which considers the properties of space and time in accelerating frames (Ie. Gravity) of reference.
 Cosmology  which considers the properties of space and time in the Universe at large.
The Conclusions Drawn from Relativity
Some of the conclusions which can be drawn from the mathematics of relativity are:
 As spacial lengths are compressed we observe that time is proportionally stretched. Therefore Time is in fact a "dimension" the same as the normal three spacial dimensions. We therefore can observe four dimensions around us.
 Energy and mass are mathematically equivelant, therefore it is reasonible to assume that they are in essance the same.
 Space in a gravitational field is contracted.
 Time in a gravitational field is dilated.
 The frequency of light is Red Shifted in a gravitational field.
 The speed of light is slowed in a gravitational field.
 Light rays are bent by gravitational fields.
 Space and Time are equivalent
 Space and Time have a beginning
 We live in a multidimensional universe.
