Question: why is a lot of science theory

Iain Bethune answered on 25 Jun 2015:

Theory is one of the three major parts of science (the other two being experiment and more recently, simulation). A scientific theory is a description of how some physical process works. A good scientific theory should be explanatory i.e. it explains why we observe things the way that we do, and it should also be falsifiable – which means it should make predictions about things that we have not yet observed, so we can do new experiments and possibly either confirm the theory, or prove it to be false.

In one sense, scientific theories can never be absolutely proven to be true (since it is always possible some new experiment will produce data that disagrees with the prediction of the theory). However, large bodies of data backing up theories causes us to gain confidence in those theories, or at least understand where they apply, and where they do not apply. For example, we have a lot of confidence in Newton’s Laws of motion – they are what describe how everyday objects move and interact. But we know that they don’t work for very small objects (where quantum theory takes over), or for objects travelling very fast (where we use general relativity).

The most important thing about scientific theory is that it is Nature that we must rely on, theories are only descriptions and approximations to the true nature of the world around us.