Align subscript

Question

When i put the code $(f_{\mathcal{X}},f_{\mathcal{X}}^{\partial})$ I get the following:

But I want the subscripts to be aligned. How can I do this?

Answer 1

As you've noticed, LaTeX will shift down a subscript when there is a superscript above it to make room. What you need to do is have LaTeX pretend there is something in a superscript above. You can do this by adding a superscript to the first f of \vphantom{\partial}:

$(f^{\vphantom{\partial}}_{\mathcal{X}},f_{\mathcal{X}}^{\partial})$