Universe and black holes I know that the radius of the observable universe is about 46.6 billion light years and is expanding at every instant of time due to dark energy . So is it possible that we our entire universe could be inside a black hole and that the edge of our observable universe represents the event horizon which in this case is expanding faster than the speed of light due to matter being constantly accreted inside it . Where that black hole is a part of another universe and that universe of another black hole and the pattern goes on . Is this possible ?
I know that the radius of the observable universe is about 46.6 billion light years and is expanding at every instant of time due to dark energy.


There's some ambiguity about dark energy. It's said to be responsible for the accelerating expansion of the universe as opposed to the expansion. See the Wikipedia dark energy article where you can read that the term "dark energy" was coined by Michael Turner in 1998. This was in a paper that referred to the type 1a supernovae observations made by the Supernova Cosmology Project and the High-Z Supernova Search Team. Their observations indicated that the expansion of the universe is accelerating, which was contrary to expectations and led to Nobel prizes in 2011.   


  So is it possible that we our entire universe could be inside a black hole 


No. We aren't in a black hole. A black hole is a place where the vertical light beam can't get out because the "coordinate" speed of light at the event horizon is zero. As Stephen Hawking said, the universe is like a black hole in reverse, but it isn't the same as a black hole.   


  and that the edge of our observable universe represents the event horizon which in this case is expanding faster than the speed of light


The edge of our observable universe is a horizon of sorts, see Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe by Davis and Lineweaver. But it isn't the same sort of horizon as the black hole event horizon. 


  due to matter being constantly accreted inside it.


That isn't supposed to be the reason why the universe is expanding. 


  Where that black hole is a part of another universe and that universe of another black hole and the pattern goes on. Is this possible ?


Reputable people have talked about black holes as baby universes but there's no supporting evidence whatsoever. My understanding of general relativity and cosmology is such that I think such hypotheses are flat out wrong. So I would say no, it is not possible.