The Four Fundamental Forces
1. Gravity-Very weak
3. Strong Nuclear-Keeps nucleus together
4. Weak Nuclear- Radioactive decay
One of four forces that act between bodies of matter and that are mediated by one or more particles. In order of decreasing strength, the four fundamental forces are the strong force, the electromagnetic force, the weak force, and gravity.
Einstein's General Relativity
The general theory of relativity is the modern theory of gravitation, proposed in 1915, also by Albert Einstein. The central point of the theory is the principle of general relativity, which states that all observers, regardless of their state of motion, will see the same laws of physics operating in the universe. The universe is like a giant sheet stretched out, the more the mass of the object the greater the dent. ("Space-Time")
In physics, string theory is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings. It describes how these strings propagate through space and interact with each other.
Electromagnetic force, the strong nuclear force, the weak nuclear force, and gravity — together into one unified theory.