What is beyond this universe ?

Beyond the world there is Earth, and beyond Earth there is space. What's beyond space? Is it possible to find an endpoint if one keeps traveling in a straight direction in space to find out?

There is no understanding of what the universe is expanding into. We call it “The Void” and currently have no concept of it as a construct. Yet the universe is expanding at a very rapid rate into this void. Inflation is a concept that helped explain the general homogeneity of the universe. Guth proposed that the universe in its first few microseconds was only pure energy.

With this entire universe, we see today exists only as energy, in the beginning, there was sufficient energy to expand space at a much faster rate then the speed of light. Remember we are talking about inflating the container that holds space, not of traveling through space. There the Higgs Field limits travel through space to the speed of light. Space has structure. We are unable to delve into its structure currently, but we do refer to the space-time foam, denoting it has structure even if we cannot observe it, or understand it currently. So in inflation, the “ball” that was the universe say at the size of a basketball, was expanded in an instant to the size of our solar system. This instant was literally approximately microseconds. We have recently determined that the universe as we know it is 71% Dark Energy. Could this be the energy of inflation? It is expanding the universe even as we speak. Expanding on what? We honestly don’t know.

The question is did the universe stop inflating, or has it continued to inflate, and consequently all we can see today is the visible universe which is only that which we can see. Whereas the universe that may continue to inflate can never communicate with our part of the universe, as inside that “ball” we defined as the universe inflating, we are limited to the speed of light through space, and if it has expanded beyond that speed, communications is not possible across that vast distance beyond what can be transversed at light speed. We know from studying the Cosmic Microwave Background Radiation (CMB) that the universe is about 13.73 billion years old. So that is as far as Light has traveled since the Big Bang was initiated. So that is the radius of the visible universe.

Scientists are also toying with the idea of our universe being only one of an infinite number of universes known currently as the multiverse. Using this concept universes are popping into existence almost daily, and most are random that cannot produce what has transpired in our universe because the physics of those component universes will not permit further development, as events cannot be completed. This helps eliminate the need for a creator, even in a starter role. Of course, it is just speculation at this time.