Set $\phi (x) = u(x)+iv(x)$, $x=(x_1,...,x_N)$, a $T$-periodic function in $H^1_{loc}(\mathbb{R}^N)$, that is $\phi (x) = \phi (x_1 + T ,..., X_N + T)$  for all $x$ and where $u = Re\ \phi$ and $v = Im \ \phi$. I wonder if
$$ \int_{[0,T]^N}\frac{u_{x_1}^2}{2} + \frac{v_{x_1}}{\sqrt{2}}(u-1)^2\ dx > 0$$
for functions satisfying
$$ \int_{[0,T]^N} v_{x_1}(u-1)\ dx  = \varepsilon > 0$$ for some small and fixed $\varepsilon > 0$. Any idea or help to show this would be appreciate! I am stucked. Thank you in advance.