Theory
From Simple English Wikipedia, the free encyclopedia
A theory is an idea that someone has created to explain something. Sometimes it can be difficult to understand why something happens, or how something exists, so a theory helps to explain these things.
In science, a theory starts as a hypothesis, which is like well-thought guess. Only after many tests to try to find out if it is wrong (to try to prove or disprove the theory) can a hypothesis be called a real theory. A theory can be disproved, but it is not possible to prove a theory completely, because endless tests would be needed, and some very simple things are very diffucult to prove with science or mathematics. However, some theories (known as postulates or axioms) are so close to proven, and work so well, that scientists can use them to predict and invent things.
Sometimes a theory does not explain very well how things work in the real-world. People may still use it because:
- The theory's predictions are close enough, and are useful (see approximation).
- People know what the differences are between the theory and the real-world, though they might not know why they are different.
- A better theory is still being worked on.
