Why Atoms Are Invisible
Why Atoms Are Invisible — I sometimes think this: the most important things are usually the ones we cannot see. The diligence that held a person up for a lifetime, the heart a parent poured into a child — we never saw them. We only inferred them from the things they made tremble. As with atoms, what holds up the world lay in the unseen. To be invisible is not to be absent. It only means our way of seeing has not yet reached it.
We were taught that the stone in our hand, the water we drink, the air we breathe are all made of atoms. Yet not once in our lives have we seen a single atom with our own eyes. Why does the tiny grain that builds everything remain forever invisible? Is it merely too small, or is there another reason?
Twenty-four centuries ago, the Greek Democritus imagined cutting bread, then cutting again. Surely it could not be cut forever. There must be a final grain that can no longer be divided. He called it "atomos" — the uncuttable. He had no proof, only reasoning pushed to its limit. For the next two thousand years, the atom lived only in philosophers minds, neither proven nor disproven.
In 1905, a patent clerk gave the answer. Einstein explained why pollen floating on water trembles endlessly (Brownian motion): invisible water molecules strike the pollen from every side, making it shake. He proved the existence of the unseen through a visible tremor. The reason atoms are invisible turned out to be simple — they are thousands of times smaller than the wavelength of visible light, so light passes them by without touching them. To see is for light to strike and return; on an atom, light does not strike.
- A single semiconductor chip carries circuits only tens of atoms wide. Every electronic device we use stands on the craft of arranging the invisible.
- The scanning tunneling microscope, using a flow of electrons instead of light, feels out the position of each atom and finally draws the atom "image." It did not see; it traced.
- Medical MRI reads the faint wobble of atomic nuclei in a magnetic field to look inside the body. The invisible atom reveals the invisible interior of ourselves.
玄은 가물가물 보이지 않는 그윽한 깊이를 뜻하니, 보이지 않으나 만물을 이루는 원자의 세계와 맞닿는다.
Meet this hanja in Cheonjamun →I sometimes think this: the most important things are usually the ones we cannot see. The diligence that held a person up for a lifetime, the heart a parent poured into a child — we never saw them. We only inferred them from the things they made tremble. As with atoms, what holds up the world lay in the unseen. To be invisible is not to be absent. It only means our way of seeing has not yet reached it.
