There is nothing beyond the observable universe but more universe to observe. The BB was not an explosion/expansion of space. It was an acceleration in time event. F=ma. Neither mass nor Acceleration is defined. Infinite mass/Infinite acceleration. And as Syndrome would say, if you have everything, then you have nothing. E=mc. Acceleration is now limited. But mass is not. That creates an infinite universe accelerated in time. Now the fun part. Mass is infinite which means its 0. Which means all you have is acceleration. As Einstein said. Motion is absolute. All there is is motion. Everything is an emergent property of acceleration. And acceleration is not a tangible thing. You cant touch it or taste it. But you can messure it. The object went from A to B creating distance. Distance is length which is a property of space/mass. You now have space and time (number of footsteps) arising out of acceleration. The objects themselves? E=mc. The conversion of radiant energy to atomic and back via Acceleration. So E=c or Energy equals Acceleration limited to the speed of light. See now why every single 'genius' who stuck there heads out of the 'mass attraction' rabbit hole promptly went back in. If mass is not a force then it doesn't exist. All there is is acceleration. And pray tell. What is acceleration? Newton's law of motion, F=ma, force comes from Acceleration of the mass. Where does Acceleration come from then. Back into the rabbit hole. Gravitational attraction. Einstein. Motion is absolute. All there is is acceleration. Where did acceleration come from then? Back into the rabbit hole. Mass (which Galileo clearly showed is not a force) magically warps space creating acceleration. Nobody can explain what acceleration in that they dont know where acceleration comes from. There has to be an outside force that created the initial acceleration event and placed the universe in an accelerated state. F=ma. An infinite, unbounded universe, everything and yet nothing. E=mc. Infinite mass. Finite acceleration. Infinite = nothing at all and at the same time, everything. There is nothing outside the observable universe and yet there is everything.

You are explaining you guess with other guesses. We don't even know if the observable universe is homogeneous.