\phi and \varphi are swapped

[s-arambillete]

Typing \phi produces φ (U+03C6 GREEK SMALL LETTER PHI), while typing \varphi produces ϕ (U+03D5 GREEK PHI SYMBOL). The look of these characters is switched with respect to the standard LaTeX output for these commands.

See Wikipedia for details on the Unicode representation of the letter phi.