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The lower bound for prime gaps

Let $p_n$ denote the n-th consecutive prime number and $g_n=p_{n+1}-p_n$ a prime gap. There are many results about the upper bound for $g_n$. Some of them still has astatus of conjecture, such as Firoozbakth conjecture ( in a prime gap version ): $g_n<p_n\left( \sqrt[n]{p_n}-1\right) $ , $\forall n\in N$, and its consequence $g_n<\sqrt{n}$ , $n\geq 3645$ . Currently the best known proved result on upper bound is $g_n\leq p_n^0.525$ ( Baker-Harman-Pintz Theorem ). Heuristic and a few calculations that I made, suggest for upper bound:

Conjecture :
$\frac{g_n}{\log{g_n}}<2\log{n}, n\geq 5 $

If we combine Conjecture with B.K.P. Theorem we get $g_n<1.05\log^2{n}$ , with Firoozbakth Conjecture we get $g_n<\log^2{n}$, which seem to be in contradiction with A.Granville proposition :$\limsup_{n\longrightarrow\infty}\frac{g_n}{\log^2{p_n}}\geq 2e^{-\gamma}\approx 1.1229$. There is also a simple consequence of Conjecture providing the lower bound for a prime gaps:
Proposition $$g_n>\left( \frac{p_{n+1}}{p_n}\right) ^{\frac{n}{2}} , n\geq 2$$
Proof: $$\left( \frac{p_{n+1}}{p_n}\right) ^{\frac{n}{2}}=\left[ \left( 1+\frac{g_n}{p_n}\right) ^{\frac{p_n}{g_n}}\right] ^{\frac{n.g_n}{2p_n}}<e^{\frac{n.g_n}{2p_n}}<e^{\log g_n}=g_n$$ ( follow from Conjecture and $\frac{p_n}{n}>\log n$) .

Question: Is conjecture plausible? Can it be proved or disproved? If Conjecture is not true, can we prove the Proposition , now taken as Conjecture, with other means?