When we talk of samadhi, people normally confuse that the yoga Samadhi with gnana Samadhi.
Is there a difference ? because, in the yoga too the oneness of the seer, seeing and the seen is what is experienced in the Samadhi. And this seems to be the case with the vedantic gnana Samadhi too. But, if it be said, in Vedanta Samadhi it is accepted that only the seer remains, it is old wine in new bottle.
This argument is taken to a next level by some vedantins themselves, by trying to show the Samadhi and deep sleep as one.
So, what is the difference ? this is, the yoga Samadhi no doubt speaks of the oneness in a way to speak. But, this oneness is attained by the control of the thought-functions (vritti). And , this thoughtless (!?!) state is the same state attained in the deep sleep, so we can easily conclude it is not what the Vedanta teaches. But is sleep not similar to Samadhi, no, it cannot be, because the sleep is a kind of avidya vritti. This is explained in the yoga sutra, “abhava alambana vritti nidra”.
Ok, it is understood the sleep is not Samadhi. But still the difference between the yoga and gnana Samadhi is not explained. It is this the yoga Samadhi as explained earlier is cessation of thought function. And the gnana Samadhi is the one which is gained through the pramanic knowledge. Through the pramanic knowledge a vritti which is akhandakara vritti is generated and this is the one which destroys all the ignorance. If the akandakara vritti is a vritti then how is it negated, because though it negates the other vrittis, it will remain unopposed ? the akandakara vritti is like the fire, when there is fuel the fire burns, and when the fuel is burnt, the fire gets extinguished itself. There is no new effort needed, in the same way, for negating this akhnandakara vritti too.
This is why the yoga Samadhi is termed, Jada Samadhi (Jada – inert) and vedantic Samadhi is called gnana Samadhi.