3D Bubble universe..jpg

Is it possible that our universe is a 3D (spacial) bubble in an infinite 3D universe, without resorting to a fourth spacial dimension ? Do the maths work?

The picture is a 1D representation of what I mean: B is the infinite universe, A is our bubble universe and C is the intersection, the origin where our Big Bang presumably would have happened. If the 1D representation is mathematically valid, what characteristics would one expect from a 3D version? Would it resemble our universe from within the bubble? Would the point of the big bang still be everywhere, or would there be a point of origin somewhere?

I might need a new thread for this.