I am getting an error when I type:
$\~{c}_{it+1}} = c_{it+1}$
The error says:
You can't use `\spacefactor' in math mode. ... composite future consumption good $\~{c}
How I can modify the code so I use the accent above c_{it+1}.
You want
$\tilde{c}_{it+1}} = c_{it+1}$.
Some accents have mathematical meaning, hence the warnings or errors.