It is easier for me to imagine an infinite universe, than it is to imagine and infinite inner universe. Still, that does not mean that there is a limit to inner space. It just seems like more difficult a concept to imagine. There is also no guarantee that the universe is infinite as well. There very well could be a boundary to the universe. If that is the case than one has to ask the question of what is beyond that boundary. Perhaps the biggest and only true problem in science is the human minds inability to truly grasp the universe we live in. I, and indeed we all; keep trying though. So, is there a limit to the inner universe. I hate touching this question, because that requires delving into the world of quantum mechanics. One has to, it is a boundary that must be passed into the infinitely small.
We all know that matter is composed of normal matter is composed of protons, neutrons, and electrons. The only exception is hydrogen, no neutron is present in its nucleus. These particles make up atoms, that combine to form compounds. Beyond this level is the field of quantum physics, the study of the very small. Quarks, Leptons, and Bosons are the subatomic components to protons, neutrons, and electrons. Beyond this, who knows. Perhaps sub atomic particles are made up of smaller particles or sub-subatomic particles. Is there a never ending spiral into an infinite smallness? Probably not, at some point it is reasonable to assume that we reach pure energy. Perhaps energy can be rolled up to form a sub atomic particle and those sub atomic particles make up particles, atoms, and so on. Perhaps the way energy forms a sub atomic particle determines the behavior of that particle. Hence there are six Flavors of Quarks, six types of Leptons, and twelve types of Gauge Bosons.
Is the energy boundary the limit? Once you have pure energy, it is easy to imagine something getting smaller and smaller, because there is no solid component to the object. There is no object, only energy. In my minds eye I can imagine a journey into infinite smallness. At the same time this notion seems out side the realm of possibility. However, the same thing can be done with traveling into outer space. It seems so much easier to imagine getting bigger and bigger vs smaller and smaller. And yet the same process is used. I can imagine space as infinite in either direction. Is this the case? You don’t need matter or energy for this experiment. In fact, lets remove both and just consider an empty void. Imagine the universe as containing no energy and no matter. Is this possible? It seems that matter could be inherently linked to the concept of space. If nothing existed then there would be no limit to smallness because nothing would exist. After all, one cannot have size when no object exists to consider. Size seems to be at the center of the notion of infinite space. When I try to conceive of an object getting smaller and smaller or bigger and bigger I seem to reach a limit. Even when you consider that an atom is mostly empty space. If you removed that empty space to the limit possible than an object cannot get any smaller without shedding parts of itself. Is this what happens with a black hole? Is there a limit to the amount of mass that can occupy a given amount of space? I assume that when an object implodes to form a black hole, matter is rearranged to allow for as little free space as possible between atoms; as well as within the atoms themselves. In this case there is a limitation to how much matter can exist in a given amount of space.
What if we consider all of the matter in the universe as being converted to free energy? There would then be no limitation, would there? Could we then squeeze all of the matter in the universe into one tiny space? The big bang theory and the singularity comes to mind. The problem here is that inner space is infinite than theoretically all of the energy could implode on itself indefinitely. So there must be a limit here as to how much energy can occupy a given space. Its either that or there is a limit to inner space. A boundary exists to smallness. One has to assume this boundary exists if you believe in the big bang, because there would have been no reason for the singularity to expand or explode. This creates a stranger notion for me that something with no mass can still have a limit to how much of it can occupy a given amount of space.
Considering infinite largeness, using all of the matter in the universe. If you could get all of the matter in the universe together without it imploding under the weight of its own gravity, then what? There is a finite amount of matter in the universe, so once we have our big ball of matter, what is beyond this? Again, the answer is empty space. A vacuum that goes on forever, and ever. The only real way to consider the question of an infinite inner space is when you do not consider matter or energy. Remove them from the equation and only consider the vacuum. It then becomes easier to imagine infinity going both ways. This imaginary universe does not exist though, the only one that does (that we know off) is this one. One in which matter and energy are everywhere. And in this universe there seems to be a boundary to the infinitely small, but not the infinitely large. Then again, this could be a product of our daily lives. Matter is all around us, and we live on a big ball of it. In the end it may be that we live in a matter zone. At this stage, the one we live on there are quantifiable sizes to things. Once you get beyond matter into the farthest reaches of our universe there may exist a vast empty, infinite beyond. The same may go for the inner verse. Once you get beyond the boundary of matter and energy, there may be another void. One that expands forever into the infinitely small.
At the end of the day this is nothing more than a fun exercise for me. I like to ponder these questions, but I do have certain conclusions that I believer more than others. Anyone that has read my paper on the Nothing Universe knows what I believe we will find if we go far enough out into space. That hypothesis has the infinite beyond as being composed of an undiscovered, super symmetrical atom composed of both matter and anti matter. The combination of which forms the true essence of nothing. That hypothesis does not preclude the existence of a infinite inner universe. All be it one that did not exist before the creation of the universe as we know it. And yet, it is easy for me to envision space existing between the particles within the nothing universe. So, it may just be that the structure of the nothing universe suffers from a limitation of scale. Once that limitation is breached than an infinite inner universe free of matter may still exist within the Nothing Universe. If you are confused than I would suggest reading my article on a nothing universe. To go into it now would take way too long. For now I have to conclude that there is a strong possibility that there is no limit to inner space, and that it may be infinite after all. As much as I find that notion illogical, I can’t dismiss it.