Quantum Mechanics (9/19)

What I found most interesting about classical physicists is how simplistically they viewed the world. They functioned by way of the clockwork model of the world. They believed that everything in this world was certain. Each “gear” of the clock moved in a very specific way and had an impact on another “gear.” Thus, physicists only had to find out what made each gear “turn” so to speak. Everything in the world could be explained to the last detail it seemed. In our time, especially with the dawn of Quantum Mechanics, scientists feel that much in this world is unknown and will stay that way. Science continues to surprise us.

Everything about Quantum Mechanics blows my mind. It is hard for me to grasp principles that seem to just be made up. Do we live in such an age that particles can move through objects like ghosts? There just is no way that I can throw my binder full of readings for this class at the wall and have it end up in the other room. If anything, I’ll just have pages upon pages of physics and history articles scattered around my room. However, Quantum Mechanics says that there most certainly is a possibility for my binder to end up in Sarah’s room.

Speaking of things being “certain,” Heisenberg’s uncertainty principle is stupefying. His thinking is much unlike that of previous scientists, especially classical physicists, who though that any variable could be measured precisely. The principle implies that variables cannot be measured completely independent of each other. Heisenberg’s uncertainty principle states that the product of the uncertainty in one variable with the uncertainty in the other variable has a fixed lower limit. For this reason, even if everything is done to make sure that a measurement is precise for one variable, the precision of the measurement of the other variable goes down. This is a little counter-intuitive to what we think about the measurement of variables in the world.

I feel like Quantum Mechanics speaks of a world in which everything is uncertain and anything can happen. You cannot rely on locality or causality in this phase. In mixed states everything and anything is possible. For example, I can be sleeping and awake at the same time. Schrodinger showed this is his cat thought experiment, where, according to Quantum Mechanics, a cat in a room with poisonous gas could be both alive and dead at the same time because there is a 50% chance of each outcome happening. This kind of stuff is just unthinkable in real life.

This craziness brings me back to the beginning of my blog. A principle driving Quantum Mechanics is that particles can pass through each other, and these particles can even pass through obstacles. It is hard for me to believe that my throwing my binder at the wall will cause it to move into my neighbor’s room, but this is possible with miniature particles. In a process called quantum tunneling, small enough and fast enough moving particles can pass through obstructions. While it is still amazing to think that these types of things can happen to small particles, I am thankful that these concepts do not apply to larger objects. Imagine what life would be like if they did!