On stability conditions for the quintic threefold

We study the Clifford type inequality for a particular type of curves $C_{2,2,5}$, which are contained in smooth quintic threefolds. This allows us to prove some stronger Bogomolov-Gieseker type inequalities for Chern characters of stable sheaves and tilt-stable objects on smooth quintic threefolds. Employing the previous framework by Bayer, Bertram, Macr`i, Stellari and Toda, we construct an open subset of stability conditions on every smooth quintic threefold in ${\mathbf{P}}_{\mathbb{C}}^4$.