Uh just checking why they call:

The theory of Reletivity a THEORY. If it is true.....
And the Big Bang Theory.?
any ideas

Anything that cannot be created or recreated will always remain a theory.

These theoty's are as true as can be without actually doing an experiment to prove them.

You can have a theory that helps prove another theory. But they are always just theory's .

Of course they are theories, because they are just beliefs. We choose to believe in something and to proclaim it as "fact". But we have no certainty of actually 100% knowing that we are somehow decieved in this perception of life. It just comes down to believing in what we think is true and false.

General Relativity is a theory. Quantum mechanics is a theory. and they do a damn good job of explaining the movement of small and large objects, because they are based on mathematics. If you cant find a mathematical basis for a theory then it will not be taken seriously, because math is the only reliable form of truth.

I've always considered theories as very educated guesses. Then next in line would be opinions.....but, that's my opinionated theory.

lets look at the terms involved here:

Dictionary.com says Theory: 1. A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena.
2. The branch of a science or art consisting of its explanatory statements, accepted principles, and methods of analysis, as opposed to practice: a fine musician who had never studied theory.
3. A set of theorems that constitute a systematic view of a branch of mathematics.
4. Abstract reasoning; speculation: a decision based on experience rather than theory.
5. A belief or principle that guides action or assists comprehension or judgment: staked out the house on the theory that criminals usually return to the scene of the crime.
6. An assumption based on limited information or knowledge; a conjecture.

one definition from dictionary.com for LAW:A statement describing a relationship observed to be invariable between or among phenomena for all cases in which the specified conditions are met: the law of gravity.

They are called theories becouse they have not been proven to be true for all possible existing cases-even if they work for all math/physics now-who knows about tommorrow.

You're obviously not familiar with my math!

The reason they are referred to as theories harkens back to the 1920's. when the famed scientist Karl Popper advanced the notion that, in order to be credible and logical, a theory must be falsifiable. In other words, if a theory has the ability to be shown to be true, it must also have the ability to be shown to be false.

Falsifiability is so important that it is, today, considered to be one of the five pre-requisites of scientific methodology, without which no idea can ever claim to be scientific. Without falsifiability, an argument can be created for anything, despite being incorrect. For instance, let's say that I wanted to prove that telekinesis exists, and to support that idea, I offer a spinning psi-wheel as proof. If the wheel does not spin, however, that is evidence that the person simply doesn't believe enough in themselves, and is obstructing their psychic flow.

This is an unfalsifiable idea: If the wheel spins, it means telekinesis exists; if it does not, it means that the person isn't concentrating enough. There is no way to show that telekinesis is not present, and therefore there is no way for the theory to be wrong, even if it so happens that telekinesis doesn't exist.

So, what would be a falsifiable theory? Let's take the Pythagorean Theorem. This theory states that the sum of the square of two side of a right triangle will be equal to the square of the hypothenuse: A^2 + B^2 = C^2. Examples of this abound everywhere (Guiness Book of World Records records it as the most independently proven theory in existence). How would we falsify it, however? Quite simple. In order to prove the theory wrong, we would simply have to find a right triangle in which the sum of the square of two side of a right triangle does not equal the square of the hypothenuse. Hasn't happened yet, and likely never will, but since it is impossible to claim that, in all eternity, no one will ever discover such a triangle, we cannot call the Pythagorean Theorem a fact, but rather, a scientific theory, which is as close as science will ever get to calling an idea a fact