What are improper lengths and improper time intervals?

[bernhard.rothenstein]

Please tell me what is the name of a length which is not a proper one and of a time interval which is not a proper one.
Thanks

 

[1effect]

They are respectively "coordinate length" and "coordinate time". You can find these in most relativity books.

 

[bernhard.rothenstein]

terminology

They are respectively "coordinate length" and "coordinate time". You can find these in most relativity books.

Thanks. Please give me some quotations.