Theories are:
"hypotheses that have survived extensive testing and repeated verification." --- American Geophysical Union
I figure that laws are theories that have been proven to occur ALL THE TIME.
But this isn't a debate about that.
Scientific Law: This is a statement of fact meant to describe, in concise terms, an action or set of actions. It is generally accepted to be true and univseral (sic), and can sometimes be expressed in terms of a single mathematical equation. Scientific laws are similar to mathematical postulates. They don’t really need any complex external proofs; they are accepted at face value based upon the fact that they have always been observed to be true.
Specifically, scientific laws must be simple, true, universal, and absolute. They represent the cornerstone of scientific discovery
, because if a law ever did not apply, then all science based upon that law would collapse.
Some scientific laws, or laws of nature, include the law of gravity, Newton's laws of motion, the laws of thermodynamics, Boyle's law of gases, the law of conservation of mass and energy, and Hook’s law of elasticity.
Theory: A theory is more like a scientific law than a hypothesis. A theory is an explanation of a set of related observations or events based upon proven hypotheses and verified multiple times by detached groups of researchers. One scientist cannot create a theory; he can only create a hypothesis.
In general, both a scientific theory and a scientific law are accepted to be true by the scientific community as a whole. Both are used to make predictions of events. Both are used to advance technology.
In fact, some laws, such as the law of gravity, can also be theories when taken more generally. The law of gravity is expressed as a single mathematical expression and is presumed to be true all over the universe and all through time. Without such an assumption, we can do no science based on gravity's effects. But from the law, we derived Einstein's General Theory of Relativity
in which gravity plays a crucial role. The basic law is intact, but the theory expands it to include various and complex situations involving space and time.
The biggest difference between a law and a theory is that a theory is much more complex and dynamic. A law describes a single action, whereas a theory explains an entire group of related phenomena.
An analogy can be made using a slingshot and an automobile.
A scientific law is like a slingshot. A slingshot has but one moving part--the rubber band. If you put a rock in it and draw it back, the rock will fly out at a predictable speed, depending upon the distance the band is drawn back.
An automobile has many moving parts, all working in unison to perform the chore of transporting someone from one point to another point. An automobile is a complex piece of machinery. Sometimes, improvements are made to one or more component parts. A new set of spark plugs that are composed of a better alloy that can withstand heat better, for example, might replace the existing set. But the function of the automobile as a whole remains unchanged.
A theory is like the automobile. Components of it can be changed or improved upon, without changing the overall truth of the theory as a whole.
Some scientific theories include the theory of evolution, the theory of relativity, the atomic theory, and the quantum theory. All of these theories are well documented and proved beyond reasonable doubt. Yet scientists continue to tinker with the component hypotheses of each theory in an attempt to make them more elegant and concise, or to make them more all-encompassing. Theories can be tweaked, but they are seldom, if ever, entirely replaced.
Real scientific theories must be falsifiable. So-called "theories" based on religion, such as creationism or intelligent design are, therefore, not scientific theories. They are not falsifiable and they do not follow the scientific method.
Wilson, Jerry. "Scientific Laws, Hypotheses, and Theories." Our Science Page. 28 April 2009 <http://www.wilstar.com/theories.htm>.
It is a lot to post, but these misconceptions really need to be cleared up.
