How Do We Know How Small An Elementary Particle Is?
“But here’s the thing: we don’t know that this is true. Sure, the Standard Model says that this is the way that things are, but we know that the Standard Model doesn’t give us the final answer to everything. In fact, we know that at some level, the Standard Model must break down and be wrong, because it doesn’t account for gravity, dark matter, dark energy, or the preponderance of matter (and not antimatter) in the Universe.
There has to be something out there more to nature than this. And maybe it’s because the particles that we think are fundamental, point-like, and indivisible today actually aren’t. Perhaps, if we go to high-enough energies and small-enough wavelengths, we’ll be able to see that at some point, between our current energy scales and the Planck energy scale, there’s actually more to the Universe than we presently know.”
Are the fundamental particles that we know of truly fundamental? Are they point-like entities, with no finite size, no internal structure, and no capacity to ever be split apart into smaller entities? According to the Standard Model, they are. But observationally, we know that the Standard Model isn’t all that there is. Moreover, we’ve got a long way to go (some 16 orders of magnitude) from our present experimental limits to the Planck scale, and what we think of as “fundamental” could undergo a revolution at any place, without any warning, if only we dare to look.