My understanding of Space, Time and spacetime

[Spacie]

...which means you haven't understood what I wrote at all. The string certainly does break, as any reliable textbook that discusses this will confirm. Go back and carefully read what I wrote again, and read the the rest of the thread it was in.

Ok, I read the first 3 pages of that thread and stand my grounds. Sorry. I find the whole topic distasteful. You think otherwise and that is fine. Let an actual experiment decide.

It breaks in every frame. SR says that objects are longer in their rest frame than in a frame in which they move. So if an object keeps a constant length in a frame in which it accelerates (as given in this scenario), then it must increase in length in its rest frame (proper length).

SR says that objects appear shorter in a frame in which they move. In comparison with the frame where they are at rest. Everything shortens in the moving frame, objects and space that houses them.

Only in their initial rest frame, they are moving in unison. In the accelerating frame they are moving apart.

-? In the first 3 pages of that thread everyone agreed and it was stressed several times that the distance between ships stays the same, including during acceleration.

It is irrelevant how you define your "objects". You can break a single object, if you enforce a constant length in a frame where it accelerates.

I disagree. In my book, all objects that are at rest in respect to each other constitute the same frame. Otherwise, all objects should break all the time. IN REAL LIFE.

And that transformation says that an object must elongate in it's rest frame, if it keeps a constant length in the frame where it accelerates.

No it does not. It says that objects appear shorter when they move fast in respect to observer (to that observer only!).

Without defining what "really" and "appears" is, this is a meaningless statement.

Yes, I had an epiphany last week that SR is all about appearances, about how things are not what they seem, how the same thing will look different for various observers. That's because the speed of light is a constant and Lorentz transform will make things look shorter at high speeds; and gravity bends light, making an object appear in a wrong place; and no object may be seen moving faster than c, because you see only what light delivers and its speed is fixed. Basically, what it says is that you should not trust what you see, especially if you're moving fast in respect to what you're seeing. That's what I understood last week, and for this I thank this forum.

 

[A.T.]

SR says that objects appear shorter in a frame in which they move. In comparison with the frame where they are at rest.

They don't "appear" shorter. They are shorter.

In the first 3 pages of that thread everyone agreed and it was stressed several times that the distance between ships stays the same, including during acceleration.

The distance stays the same in the initial rest frame of the rockets. It does not stay the same in all frames.

That's because the speed of light is a constant and Lorentz transform will make things look shorter at high speeds; and gravity bends light, making an object appear in a wrong place

Wrong. It is not about how objects "look". In fact a fast moving object would not look contracted:
http://www.spacetimetravel.org/fussball/fussball.html

Length contraction is not what you see. It is what is left after you account for finite light speed to calculate the actual size of the object

That's what I understood last week, and for this I thank this forum.

Well, your understanding is completely wrong. So no need to say thanks.