By default, WordPress Twenty Thirteen theme do not display author byline in the post metadata unless it is on multi-author blog . And the reason why Twenty Thirteen theme takes the such way on handling author byline is becomes logical, since it is a fact that displaying author byline in the post metadata is pointless expect for multi-author blog.

Therefore in case you have a single author blog and want your name displayed as a byline in the post metadata, it is required for you to make your blog multi-author. thus you need either a guest-author or create new author (it doesn’t have to be a real one) and publicly publish at least one post for them. As a bonus, your (author) bio will be displayed underneath your posts if you have your description in your user profile filled in.

Yes, the above required step is the simple yet annoying way to get Twenty Thirteen theme displays author byline in the post metadata on your single author blog, since hardcoding your theme is not recommended unless you know at least a basic understanding of how PHP works.

Alternatively, displaying author byline could also be done by adding a little css trick to your child theme css:

.single-author .entry-meta .author { display: inline }

Notice: no author bio displayed underneath your posts.

Choose the simplest one :
play the css, or
let’s sing: Here’s come dummy authors…

The people who most heavily rely on pseudonyms in online spaces are those who are most marginalized by systems of power.“Real names” policies aren’t empowering; they’re an authoritarian assertion of power over vulnerable people.These ideas and issues aren’t new (and I’ve even talked about this before), but what is new is that marginalized people are banding together and speaking out loudly. And thank goodness.

Danah Boyd on “Real Names” Policies Are an Abuse of Power