There is a distinction -- in my view -- between the non dual Brahman that Vedanta talks about and the nondual that Abhinavagupta describes in Monism of the Kashmir Shaivism. The first one states that Brahman alone is real and everything else is unreal. This seems to be about subject and object. It concludes that Brahman is the only real thing and all else is mithya, false or unreal. Whereas the Abhinavagupta's nondual seems to be stating consciousness and energy are not two separate phenomenon, but they are one.