# The Bra-Ket Notation in LaTeX

I want to write the following symbol in LaTeX:

I'm using the following (minimal) code:

    \documentclass[12pt,twoside]{article}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{amsthm}
\usepackage{amsfonts}
\usepackage{braket}

\begin{document}
$$\ket \psi{(t)}$$
\end{document}


I don't however get the desired result. The $t$ symbol appears outside the ket, as opposed to the output in the figure. How do I fix this?

you've placed the (t) outside the scope of the \ket command.

just move the open brace before the \psi:

\ket {\psi(t)}.


off-topic: since amssymb loads amsfonts automatically, it's not necessary to specify them both.

• Awesome. Btw, if you can, please do introduce a tag for "Braket" over here. I think that'd be helpful. Jun 27, 2016 at 14:00
• @JunaidAftab Well I actually just created the tag by accident, but I didn't mean to! Tags are about indexing similar questions, they're a filing system essentially. As it says on the privileges page "You should always favor existing tags; only create new tags when you feel you can make a strong case that your question does cover a new topic that nobody else has asked about before on this site." Tags aren't about providing a list of contents for your post. They should be broad. And braket notation simply isn't a LaTeX topic. Anyway, welcome to the site and +1 barbara Jun 27, 2016 at 14:13
• @Au101 -- at first i entered this as a comment, thinking there would be a previous question that had an appropriate answer. but nothing suitable came up. however, there are numerous questions about this package (as well as a lot of misspellings of regular brackets). so i'd favor a dedicated tag for the package, and would help "clean up" prior questions and "misdeeds". Jun 27, 2016 at 14:23
• Oh, fair enough :) well now we have one :P I had also overlooked the braket package. Sorry for the mess, but I think we got there in the end :) Jun 27, 2016 at 14:25