Unexpected number appears

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I am working on estimating norms of solutions of the simplified version of the Fokker-Planck equation$$ u_t=\text{div}(b(x)u)+\text{div}(a(x)\nabla u) $$ with $\text{div}\in L^q(\mathbb{R}^d)$ using mainly Functional Analysis inequalities. I was computing the ratio between powers of norms of the solution when suddenly the following number appears$$ \frac{3+\sqrt{5}}{2} $$ Is this number somehow important, other than it's the golden ratio plus $1$? And how does that number even appear on Functional Analysis or PDE? I was quite surprised and curious. Any ideas?