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So, I know that SR makes two statements.
One is the first assumption it has:
"Speed of light is the same with respect to all reference frames".
Second, the statement:
"A photon cannot have a reference frame".
(Please correct me if the statements I wrote are not accurate.)
Aren't these two statements a bit paradoxical?
One first says that Speed of this thing is the same with respect to all frames. And then says speed is not defined wrt to it's own frame, because there is no such frame.
The comparison has already been made in assumption one. It's not logical to say in the next statement the opposite, and say that no we are just not comparing with it's own reference frames. It's a contradiction.
Are Physics textbooks not accurate enough? or have I made a mistake somewhere in my thinking.
I don't really want to be correct, but just want to know my mistake.
But, so far, it seems like a Philosophical mistake in SR.
Any statement is only valid under the assumption applied on top of it.
I understand that the photon cannot have a frame of reference, but what I am pointing to, is that a comparison with "All" reference frames has already been made earlier. Before this statement is established that "Photon cannot have a frame of reference".
You cannot compare without defining. This seems like a paradoxical set of statements.
If you look at the current answers, this is exactly what I am referring to. We have a reason from statement 1 itself for statement 2 to be true, but if statement 2 is true, then it violates part of statement 1, because both cannot be absolutely true together.
I agree that statement 2 will follow from statement 1, but if statement 2 follows, then statement 1 cannot be absolutely true, because it was stated first. Statement 2 follows from it through reasoning.
Let me illustrate what I think could be wrong:
We make statement 1: "Speed of light is same wrt to all reference frames"
These statements are a subset of statement 1:
Statement A: " Speed of light is same wrt to A reference frame"
Statement B: " Speed of light is same wrt to B reference frame"
Statement C: " Speed of light is same wrt to it's own reference frame".
If 1 is true, then A, B , and C all are true, so far.
But, now we say that it follows from 1, that C cannot be true, because there can be no reference frame for photon. This constitutes a contradiction, because C has already been said to be True.