It is not know that RH implies EH, or that EH implies RH. Let us denote $$S(x):=\sum_{p_n < x} (p_n -p_{n-1})^2.$$ Assuming the Lindelöf hypothesis, Yu (1996)Yu (1996) proved that $S(x)\ll_\varepsilon x^{1+\varepsilon}$. Unconditionally, Stadlmann (2022) proved that $S(x)\ll_\varepsilon x^{1.23+\varepsilon}$.