Usage of 无 compared with 没有 I just stumbled across a new phrase 无消息。

This is the first time I've encountered 无.

How it is used, and how it is different from 没有，as in 没有消息？
It is hard to give a rule on using 无 vs 没有， even they mean the same.

Only 无 is used: 

无所谓 （We don't say 没有所谓, but some people say 没所谓）

无线电 （We don't say 没有线电）

无论如何 （We don't say 没有论如何）

无性繁殖 （We don't say 没有性繁殖）

Only 没有 is used: 

我没有钱 （We don't say 我无钱）

你没有失败 （We don't say 你无失败）

Both can be used: 

没有 消息就是好消息。 or 无 消息就是好消息。

没有 人能猜出这个谜语。 or 无 人能猜出这个谜语。



I think there are still some clues on using 无 vs 没有.


无 is more like 'non-' or "un-"in English, and 无 is used in some Idioms or fixed phrases, like 无所谓, 无论如何, 无土栽培, 无独有偶, 无恶不作 etc. In those words, we don't use 没有.
When 没有 is used for "not" in English to negate something, 没有 can NOT be replaced with 无. For example, 他没有做完作业. We don't say 他无做完作业.
When 没有 is used for "without" in English, it can be replaced with 无. But I am not sure if it is always true. For example, 无人喝彩. We can say 没有人喝彩. But if used as a tile of a book, a story, or a movie, 无人喝彩 is better, but using 没有人喝彩 is also ok.