Taken from https://en.wikipedia.org/wiki/Special_relativity


To me it seems as though these two statements contradict eachother. Does anyone else see what I mean? Am I wrong to say that these two statements appear to create a contradiction?

I'm not trying to rail against theoretical physicists btw--Im trying to understand their pov better and I got hung up on this and would like to see what people think about it.

No. Perhaps you should explain so someone can help clarify.

Yes.

1) and 2) are different things, so they don't contradict each other. I think I may see your point though.

1) The more an object's temperature differs from that of its surroundings the faster its temperature approaches that of its surroundings.
2) Ice cream never melts.

They don't have to be the same thing to be contradictions, all they need to do is propose two or more truths which cannot coexist at the same time.

You might want to explain how the original 1 and 2 don't, in your current state of misunderstanding,* cannot coexist. As mentioned, this will likely clear things up for you.**

*I am presuming that you are not going to win a Nobel Prize for discovering a great flaw (or a minor one). I will have the moderator change the word if you do.

**there may be some math. There will almost certainly be some disabusing of notions that are only correct in Newtonian physics

I will try to explain what I mean. I will note that it is concerning to hear someone imply "If you were correct in your implied distension you would be a genius, so best not to question the doctrine."

1a) Throwing a baseball while standing still.
1b) Throwing a baseball from a moving object and calculating the change in position in relation to a stationary observer.

2a) Standing still, shining a light, and calculating its speed.
2b) Being on a moving object, shining a light, and calculating its speed relative to a stationary observer.

If the laws of physics were invariant, there would not be exceptions for light. The fact that it appears there are exceptions for light means that they are indeed variant. I'm not saying that this is a truth, I'm saying that this is the meaning behind the question.

Your concept of "invariant" needs further scrutiny. What do you think that word means? Because the definition provided and your example do not cohere to it.

As has been mentioned here before, and elsewhere by scientists, you are being an idiot* if you think that you cannot question doctrine.

Unlike before (where I said you were merely mistaken), I saying you are being an idiot because it has been explained to you several times before, both here and in every science textbook that you have read, that you are absolutely supposed to question theories. It is, in fact, the entire point of the scientific method.

There isn't an exception for light (or baseballs, which can move at the speed of light just like light can and would behave exactly like light does at the speed of light in a vacuum). You are confusing Newtonian physics with Relativistic physics. Newtonian physics doesn't work at speeds approaching the speed of light. That is why Relativity supplanted it. See? Quite a simple misunderstanding. I'm feeling quite clever that I guessed what the misunderstanding probably would be.

Back to my first point, where I said you were being an idiot: Relativity supplanted Newtonian physics BECAUSE smart people did what they are SUPPOSED TO, which is to be doing EVERYTHING THEY CAN to not only question, but ACTUALLY TRY TO DECIMATE existing science!

I used caps in the above on the off-chance that your continued belief that we aren't supposed to question science is due to you never having had it yelled at you that the entire ****ing point of the scientific method is to question existing theories to arrive at better ones. It does, of course, help to have an understanding of the actual theories you are trying to question so as to form halfway decent questions and experiments to disprove them,*** which is why this post is brought to you by our sponsor, Science and Mathematics Books.

*no need to feel hurt or dismayed or offended. Everyone is an idiot in their own special way. If I thought you were more of an idiot than the average person, or incapable of learning, I would have not answered at all,** so you can feel good about that. That is, in case you cannot tell, a compliment.

**unless I were in one of my moods where I would, which I am not in currently.

***questions to develop understanding do not have such a high bar.

You're hung up on the speed of light, likely thinking that if all of the laws of physics are invariant so should be the speed of light. But the speed of light IS invariant in that it is the same for all observers regardless of their status. Whatever an observer's condition (stationary, moving, etc) the speed of light is the same. This seems counter-intuitive, hence your problem.

Your 2) is clearly false. That is a game changer.

I feel like there is some prior beef between you and Brian that I'm jumping in to, but...

Yes, they do form a paradox, which Einstein found a way to resolve with his special theory of relativity (see below).

There is not an exception for light. The problem you are describing is about "addition of velocities", where the the common sense formula v = v1 + v2 is just a very good approximation at speeds that are low with respect to light.

If you throw a baseball at 50 mph while standing on a train moving at 50 mph, an observer will measure that baseball as moving at 100 mph. In the links below you will find the correct formula to use when the speeds are a significant fraction of the speed of light:

https://courses.lumenlearning.com/ph...of-velocities/
https://www.omnicalculator.com/physi...ocity-addition

If you are on a spaceship traveling toward me at half the speed of light (0.5 c), and you launch a missile toward me at half the speed of light relative to your ship (0.5 c), I will measure that missile's speed toward me to be 0.8 c, not 1.0 c.

The exception from common experience is not for light, but for everything that moves at a speed which is at least a significant fraction of the speed of light. This is not an exception for the laws of physics, because the common sense approximation that applies for slow moving objects is so close to the correct physical law that we don't notice a difference in normal situations.

What makes this possible, and not a contradiction, is that our reference frames are related by a Lorentz transformation, not a Galilean transformation. This is an experimentally verified fact of our universe.

https://en.wikipedia.org/wiki/Specia...ial_relativity

Ryan, I can give you that the original statement isn't optimally worded. As Einstein himself said: "simplify as much as possible, but not more than that"

But if you need to go short, you have to. By the time of1905 he had to spell out 2). Now it's "natural". And Newtonian physics, however much we loved it in school, is "unnatural"

Hey cool thanks, and thanks for all the other responses in this thread. And no there is no prior beef between Brain and I, I don't know who he is.

I think that my confusion came from number 2 which specifically talked about light, but in reality it means to say "for all objects traveling at the speed of light" (I think). I thought that it was making an exception for light because of the way it singled light out, directly after making the statement that there are no exceptions.

Again, I might be wording the above incorrectly, but that was where my underlying confusion stemmed from.

There isn't. I like Ryan, with the exception of his weird belief that science is about unquestioned dogma.

I think you got it.

No. The wiki mentions two postulates: Laws of physics are the same everywhere and the speed of light is the same for all observers. Einstein takes these two separate features, does his genius thing, and here we are.

He got that the two aren't at odds. That is something.

The speed of light is the same even if there is acceleration. Why does Einstein cut out acceleration in 1)? That may be a reason the statements look a bit weird intuitively, kind of don't match. Not contradict though.

It was from an article in Special Relativity, not General Relativity.

Yes, old stuff. Thanks!

Can you dumb this down? I felt like his question was the same as what I was asking and I def wouldn't mind hearing further explanation of it. However I should probably finish doing my reading before I get into a discussion about it ttytt.

Special relativity is just a theory about objects that are not accelerating. The "special" is for "special case." Einstein hadn't figured out a more general theory that would include objects that are inertial and accelerating yet, and they were not addressed in this theory.

He then went on to develop General relativity, which is a more general (more complete as it includes more stuff) theory that includes objects that are accelerating in addition to ones that are not.

A silly analogy is that first he figured out a theory of how to cook eggs (special relativity) and then went on to figure out how to cook a full breakfast (general relativity).

Let me make that slightly more clear: special relativity only covers the cases where acceleration equals zero.

BTM to the rescue!