(i) Quantum theory- a theory of matter and energy based on the concept of quanta, especially quantum mechanics

(ii) Theory of relativity - Albert Einstein's general theory of relativity is one of the towering achievements of 20th-century physics. Published in 1916, it explains that what we perceive as the force of gravity, in fact, arises from the curvature of space and time. Einstein proposed that objects such as the sun and the Earth change this geometry.

(iii) Big Bang Theory - The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods through its subsequent large-scale evolution.

(iv) Theory of evolution - Darwin's theory consisted of two main points;

1) diverse groups of animals evolve from one or a few common ancestors;

2) the mechanism by which this evolution takes place is natural selection. This SparkNote will first take a look at Origin of the Species, and then more closely examine Darwin's theories.