PAS 6- Into the Quantum World

Quantum Chromodynamics by psion005

Atoms are made of electrons, protons, and neutrons. An atom is mostly made out of space and to put it into perspective, if a football stadium was the equivalence of the atom, a speck of sand would be the nucleus. And since everything is made out of atoms, essentially wouldn’t we be able to walk through walls just as if we were ghosts? Here things get funny when we talk about small-scale physics. There is a property called the Pauli Exclusion Principle which states two electrons can’t have the same quantum state, so at the microscopic level, the atoms are repelling each other even though matter is technically empty. Like I said, the laws of physics which normally apply to our daily lives are completely ignored and changed at the quantum level. The quantum level is important to understand because the orientation of atoms changes the way things work. In particular, by examining how electrons can work with absorbing light, we can adjust to make solar cells more efficient in converting light to electricity.

There is also another statement of quantum mechanics that states that particles can be in two places at the same time. A very common example is the Schrodinger’s cat experiment. A cat is placed into a sealed box and with a radioactive substance and a device that will calculate when this substance will decay. When it does, it triggers a device that will kill the cat. Yet as we look upon the box, we don’t know if the cat is alive or dead, and it is the act of opening the box to see if it has died or remains alive. Here the cat is at a superposition – a state of being both dead and alive and it is the act of observing something to be sure what has happened. This experiment is the reason why we coined “curiosity killed the cat”.

When we think of light we just see that it helps illuminate our path and surroundings. But at the atomic level, for the longest time, scientists believed light was a particle. And this was the center of a huge debate whether light was a particle or a wave. It was Einstein who suggested this strange hypothesis that in fact light acted as a particle and wave. Here is the evidence. It was by passing light through a tiny slits that we observed that light just didn’t pass straight through as expected. In fact, the light spread out in a wave-like manner overlapping with the other waves from the other slits. This was groundbreaking. This was clear evidence that anything that applies to our lives on the daily basis cannot be assumed and applied to the atomic and quantum levels. These types of discoveries are made and are each more mind-bending and confusing. It’s just the way the quantum world works.

Leave a Reply