If we had the technology, could we keep zooming in forever?

Question

If you zoom into something and get smaller and smaller, past atoms, past the nucleus, and just kept zooming in, would things continue to be made from smaller things? Is there some kind of "wall" we would hit where even if we had the power we just wouldn't be able to zoom any further? If you can zoom in forever, does that mean we live in a fractal, where everything is made of something smaller and is part of something bigger?

Answer 1

First, light is a property of electrons in atoms. Light is fundamentally limited to the size of atoms at their smallest resolution. Visible light, x-rays, or any other radiation is simply unable to peek at the components of atoms because of its nature. Radiation (light) is the result of the change of electrons from one energy level in an atom to another. Anything smaller than an atom, such as elementary particles, cannot be seen so its size has to be inferred.



Elementary particles each exist at a discrete point in space. They have no width. They are separated from each other by forces that exist between them, but they are not solid little billiard balls. When a diameter of a particle is given, it is really the distance they separate from each other, not the same thing as the kind of diameter macroscopic objects would have.



There is a certain limit, the Planck length, which is thought to be the smallest possible length in the universe. It is 1.61619926 × 10-35 meters and is derived from calculations. You can think of it as the absolute minimum grain size of the universe. Even if it were possible to have such fine resolution, it would be the ultimate pixel size.



Yes, there is an ultimate limit to how small a thing can be.



As for the universe being completely fractal, it's close. In a certain sense there are similarities between the very small and large, but you will not find a galaxy in an atom. The similarities are because the small, the large, and in-between are all governed by similar forces that follow similar laws. Where there are differences, that is because different laws apply.

Answer 2

So there is a fringe theory that deals in a possible fractal nature of the universe: http://en.wikipedia.org/wiki/Fractal_cosmology



The answer to your question according to the currently accepted theory, the Standard Model, is a mix between yes and no. So there are elementary particles which are not made up of anything else, like electrons and quarks. So in that sense, yes, you would hit a wall where you no longer see that matter is made up of more "things". However, at the level of an atom, quantum mechanics dominates the physics. So now your question becomes non-sensical because you would not expect to see little particles (like little BBs), rather you're just going to see distributions of particles (perhaps clouds of particles).



It becomes difficult to answer exactly what you will see at such small scales because what you would actually see depends on your instrument. Optical microscopes cannot probe atoms, so you cannot use light (photons) to see atoms, much less things smaller than atoms.

Answer 3

We don't know.



There was a time when atoms were the smallest known thing. There was speculation about what the structure could be, but no evidence about it and no way to probe.



Well now we have strong evidence about quarks and leptons, but no evidence that there is any substructure to them. Our current theories treat them as fundamental particles.



String theory could treat them as vibrating strings, which would be a form of a smaller structure. But we can't design experiments that would show evidence for this today. It's possible that we have now seen the lowest structure, but there's no way to know.

Answer 4

No. Once you get to the level of quarks there is nothing smaller to 'zoom' in on. We have no proof, for example, that electrons are made of anything smaller.