What you're saying, then, is that scientists can not test the Big Bang.
I have to be careful, I'm not a physicist but yes, we can agree that scientists are NOT making their own big bang.
They can test things that they think may contribute or result from the Big Bang, but they can't test the Bang itself. Again, this is why it remains a theory. Something becomes a Law (fact) when it is testable.
Be carefull here. You are confusing
testable with
directly observable. For the record, "laws" are still "theories". Typcially a law is simpler than a theory and thus considered more "obvious" but they are philosophically the same thing. Newton's laws survived for 300 years before they were refined!!! The indirect tests that the big bang happened are AS valid as the experiment of throwing an apple in front of the air and seeing if it comes back on the ground.
Lets get our terminology straight:
The experiment (test) is throw apple in the air at a certain velocity and direction. The theory: newton's laws allows you to predict what will happen; i.e., the apple will follow a certain path and end up on a certain place on the ground.
You observation (fact) is the path the apple follows and the location where it lands.
If your apple falls somewhere different, that invalidates your theories. Now in that example, we have several refinements, air resistance, measurement error, etc.
In the case of the big bang, your test is to observe light from several stars and do things with said light, observe its color ect. Your theory is a rather elabortate theory called the big bang. Based on that, you make predictions about what will happen. If they don't happen, your big bang theory was wrong!!!
The fact you did not make the big bang happen again is irrevalavent. Your big bang is testable!!!
Now again, remember, I am not a physicist. I am not going to tell you objectively how many experiments have been constructed to establish the big bang. Obviously there are lots. The point is if those experiments did not work, the big bang would be proven wrong.
No, of course, you see a flaw here. There may be more than one explanation for a given result. Science is inductive. That's why the concept of Ocarm's razor exists. In theory we take the simplest explanation.
Can we test the theory of relativity? No. We can test things that we expected to be a part of relativity, but we can not test relativity itself--thus, it remains a theory.
Our tests for relativity are as valid as those for Newton's laws or gravity. And yes, we can test it. Again, you've been taught by somebody without a science background.
Gravity is STILL a theory. ;-).
We can do the math, we can write out the equation, but it remains a theory because it is not testable.
Ummm, no!!!
What happened was we made some predictions using newton's laws. The results were WRONG. Relativity theory explaned those better.
The Big Bang is a theory, or hypothesis. It's based on a collection of facts and observations. We test these facts and observations and determine that the Big Bang is a plausible explanation. But, the Big Bang itself is not testable. If it were, it would not be a theory. And that's my point. It's a theory because it can not be proven. It can not be proven because it is nothing more than an idea based on a handful of facts.
That's what testable means. :-).
You cannot prove ANYTHING except mathematics. SCIENCE is inductive.

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Uggh.
What you're saying, then, is that scientists can not test the Big Bang. They can test things that they think may contribute or result from the Big Bang, but they can't test the Bang itself. Again, this is why it remains a theory. Something becomes a Law (fact) when it is testable. Can we test the law of gravity? Yes. Can we test the theory of relativity? No. We can test things that we expected to be a part of relativity, but we can not test relativity itself--thus, it remains a theory. We can do the math, we can write out the equation, but it remains a theory because it is not testable.
The Big Bang is a theory, or hypothesis. It's based on a collection of facts and observations. We test these facts and observations and determine that the Big Bang is a plausible explanation. But, the Big Bang itself is not testable. If it were, it would not be a theory. And that's my point. It's a theory because it can not be proven. It can not be proven because it is nothing more than an idea based on a handful of facts.
Yes, we can test the Big Bang based on what we predict. Yes, we have tested the theory of relativity. That's why it's a theory. They have been proven. New observations can lead us to discard this theory as an insufficient model of the universe, just like we have discarded Newton's laws as a model (though still useful).
A law is not a fact. A law is a repeatable relationship between things such as E=mc2. Gravity, is a theory. The theory of gravity is distinct from the law of gravity. The law of gravity allows us to predict how two objects fall towards each other. The theory of gravity explains the law and observations.
Understand?
Clearly he understands, his definitions are just plain wrong.