Please forgive me if this question has been asked before, but I haven't been able to find it. On Mathematics SE, what code/command/operation starts a new line without space afterwards? Thank you very much!
The following in green is what I desire. I typed the second equation in a new line after the first.
$ \color{green}{\nabla \times A = 0} $
$ \color{green}{\nabla \times B = 0} $
However, I tried to achieve the same formatting for the following two equations in red. Why doesn't it work?
$ \color{red}{= \epsilon_{ijk}\epsilon_{lmk}\partial_j \partial_lA_m} $ $ \color{red}{= (\delta_{il}\delta_{jm} - \delta_{im}\delta_{jl}) \partial_j \partial_lA_m }$