Notation Convention: Primes in Coordinate Transformations

[Steely Dan]

I have seen in various locations different conventions regarding the location of a prime symbol denoting a tensor represented in a new frame. For example, if the position four-vector is

$$x^{\mu}$$

then this four-vector in a different frame is often written as either

$$x'^{\mu}$$
or
$$x^{\mu}{'}$$

Is there a recommended convention for this, or better yet, is one of them substantially more common than the other?

 

[Ben Niehoff]

I think the more common convention is to put primes on indices, like so:

$$x^{\mu'}$$

This way, it is clear exactly which indices have been transformed to a new frame.