When I studied astronomy at the university, the first thing that you had to grasp was the immense distances involved. Even in our own solar system, the distance from the Earth to Uranus is immense. Now imagine the distance from the Earth to the Oort cloud. As the distance increases, man quickly loses all perspective. Travel far enough out, and the numbers grow so large that they no longer have names for their differing orders of magnitude. In fact, we don't even have language capable of describing the distance. The best that we can do is to say that it is "x" ly away, and even that system become cumbersome as the numbers increase. Hence scientific notation used to describe distances on a cosmologic scale.
In the video that you linked, the camera flies billions of light years. Each speck of light seen by the viewer is an individual galaxy. We know that each galaxy is comprised of billions of stars. Now imagine the number of stars represented by those galaxies. Now imagine the number of planets represented by those stars. It boggles the mind. I suppose that it all boils down to this: our place in the universe is very, very small, and that is a humbling thought.
As to your question about traveling past the universe's expansion, I would surmise that the universe is essentially an ever expanding bubble. As such, it has a barrier to contain it. If so, it would take more energy than contained within the universe to exceed that limitation. The real question is this: if the universe is expanding, and if the universe has been expanding for 13.7 billion years, then what is the universe expanding into? How much space is there to contain that expansion? If the arguments are correct for multiple universes (quantum computing, mirror universe, and such), how large is that area? What contains that space? It cannot be an infinite regression because that would violate logic and the mathematics that describe reality, therefore there is an answer. If there is an answer, then it is a number that is even larger than the number of universes such a space would contain. Imagine the distances contained in that!
We are a very small species in the grand scheme of reality indeed! Thank you for posting on this topic. It has been years since I have thought about any of this.
