Mithya is the curious ontological status enjoyed by the entire objective universe in both its gross and subtle aspects. Though the physical objects, emotions, and thoughts appear to us and are experienced by us, they are nothing more than temporary apparitions in a state of constant flux even as they appear solid and/or stationary for any given period of time. Because they are impermanent we cannot say that these objects are real, yet at the same time because we experience them we cannot say they are entirely unreal or non-existent. Moreover, further inquiry will reveal that all such objects enjoy no independent nature of their own, but are entirely dependent upon awareness, me, for their existence. We, therefore, say they are apparently or dependently real.
The whole of Vedanta basically boils down to an understanding of the difference between the real and the apparent. Vedanta refers to this in practical terms as the discrimination between the self and the not-self (i.e. atma-anatma-viveka).
Carried out to its inevitable conclusion, however, the inquiry founded upon this discrimination will ironically lead us to the realization that reality is fundamentally non-dual.
If we consider our experience of seemingly independent objects, the first realization we make is that the way we identify, recognize, and gain knowledge of any object is through the specific type of sense data we are able to gather from it. In other words, shape and color appeal to our vision, sound or absence of sound appeal to our hearing, texture and hardness appeal to our sense of touch, aromas appeal to our sense of smell, and flavors appeal to our sense of taste. In short, our analysis reveals that all objects (both gross and subtle) are only verifiable through sense perception and/or sensory-based inference, both of which occur in awareness and have no verifiable existence outside of awareness.