# Non RLT-Cutting planes for nonconvex QPs?

Consider a general nonconvex QP $$x^\top Qx$$. This can be linearized in an extended space by using the variable $$Y=xx^\top$$.

Now a valid inequality $$a^\top x \le b$$ can be strengthend by the RLT procedure by multiplying with some $$x_j$$ to obtain $$a^\top y \le bx_j$$. See for example here.

Are there other approaches than RLT in the context of nonconvex qps to strengthen a given inequality?