So in the actual article they prove they can tell one real £10 note from another real £10 note, because every plastic note accidentally has a unique random texture.
But as these are real notes, they can be uniquely identified by the serial number anyway.
They never get to a part where they explain how this technique is useful in telling real notes from fake, since fake plastic notes would also have unique textures.
But as these are real notes, they can be uniquely identified by the serial number anyway.
They never get to a part where they explain how this technique is useful in telling real notes from fake, since fake plastic notes would also have unique textures.