What are the key postulates for developing Einstein's relativity theory?

[wdlang]

i am now reading the book by landau

'the classical theory of fields'

it seems that to develop the relativity theory of einstein, only two postulates are needed

the first one is relativity

the second is no instantaneous interaction

therefore, einstein's theory can be developed in an arbitrary dimension

 

[bcrowell]

i am now reading the book by landau

'the classical theory of fields'

it seems that to develop the relativity theory of einstein, only two postulates are needed

the first one is relativity

the second is no instantaneous interaction

therefore, einstein's theory can be developed in an arbitrary dimension

There are lots of axiomatic systems that you can use to derive relativity. The one I prefer is the one given here http://www.lightandmatter.com/html_books/genrel/ch02/ch02.html#Section2.2 (statements L1-L5). I'd be interested in hearing more about Landau's system. Can you state the two postulates he uses in more detail?

If I'm understanding you correctly, I think you're saying that you'd been assuming, before seeing Landau's treatment, that relativity only works in 3+1 dimensions. I guess that's true if you start from Einstein's 1905 postulates, since Maxwell's equations are explicitly 3+1-dimensional. But light isn't really fundamental to relativity. The postulates L1-L5 in the system I linked to above work in any number of spatial dimensions.

 

[wdlang]

There are lots of axiomatic systems that you can use to derive relativity. The one I prefer is the one given here http://www.lightandmatter.com/html_books/genrel/ch02/ch02.html#Section2.2 (statements L1-L5). I'd be interested in hearing more about Landau's system. Can you state the two postulates he uses in more detail?

If I'm understanding you correctly, I think you're saying that you'd been assuming, before seeing Landau's treatment, that relativity only works in 3+1 dimensions. I guess that's true if you start from Einstein's 1905 postulates, since Maxwell's equations are explicitly 3+1-dimensional. But light isn't really fundamental to relativity. The postulates L1-L5 in the system I linked to above work in any number of spatial dimensions.

yes, light isn't really fundamental to relativity

That is the biggest lesson i learn from landau's book

landau states that there is no instantaneous interaction and there is a maximum velocity for any signal. This velocity happens to be the light velocity in 3+1 dims