What is quantum mechanics?

To put it as straight forward in as little words possible, quantum mechanics is physics, math, technology, philosophy, and many other things. It's deeply ingrained in natural philosophy, which is the questioning, investigation, formulation, and study of the nature of the physical world. Literature on quantum mechanics ranges even further, from mathematics and physics textbooks to things like spiritual science and holistic living. But to further elaborate, I must input some philosophy of my own:

Talking about quantum mechanics is much like talking about anything else; music, history, sports, the weather, math, science, your favorite foods and animals: that is, there are your own interests, ideas, interpretations of things, and then there are other's. You and a number of other people might share the same ideas, or you might not. But ultimately, trying to define or talk about anything becomes difficult, or easy, or simple, or complicated, when you try to express how you feel or understand it more and more. That's just the nature of philosophy, stream of consciousness, and conversation, mind you, so don't expect anything but argumentative commentary out of this article.

If you're wondering why I'm going deep into semantics and the abstract symbols behind speech and thought and many interpretations, it's because it's relatable to discussing quantum mechanics: it's a potential for an open ended conversation. Quantum mechanics is a subject still in development, despite having a history of many decades (and centuries, if not millennia of build-up), constantly changing with new studies, experiments, data, and consequent interpretations of what the new findings imply. Because surely, explaining things like how a toaster works can be simple enough: you put your bread in the bread-slots and press or push this button and wait. But talking about the history of toast, why you want toast, why we eat it, or what toast even is, initiates a simple examination of life's most mundane activities to a day's worth of abstract dialogue, research, hand-waving, and feeling plenty good about oneself. And this is how we begin talking about quantum mechanics.

You might relate quantum mechanics with things like physics or mind-bending explorations of the universe, or maybe even philosophy about our relationship with everything around (and inside) us. There certainly is a lot to talk about, but unlike our thoughts, we need to start with one exact place, stick to it, and add onto the conversation from there; we must begin somewhere. So all new age parallel multi-universe or existential-epistemology aside, we will start with history. There is a history behind quantum mechanics, and knowing it can give us some insight on how to talk about what we'd like even more.

Talk about "quantum mechanics" indeed did not start until a little over a century ago with research in problems relating to natural philosophy and science (i.e physics), in an academic environment much different from today's argumentative online chat forum discourse or casual cafe talk with a close friend. The individuals that pioneered conversation about what we would today refer to quantum mechanics were physicists, mathematicians/logicians, chemists, and many others. These scientists used mathematics called partial differential equations, matrix mechanics, statistics, topology, complex analysis, linear algebra, calculus of variations, and even created new mathematics and unique logic to explain everything that quantum mechanics was confusing them about. However, before anything new and startling happened, they were ordinary scientists, studying something that in their day was considered to be complete and finished. The idea at the time was that scientists already figured everything out relating to the natural world: for example, the study of basic mechanics made it possible to understand how people, planets, and even galaxies move and physically interact with their environments; the study of thermodynamics made it possible to understand how heat energy changes and interacts with different materials; and chemistry made it possible to understand that everything around us is composed of small objects called atoms. With many other studies that explained the world more and more, indeed, with so much knowledge that could model and predict the outcome of almost every physical situation, there seemed to be only but a few problems left to explore. But these early quantum explorers started their journey to understand quantum mechanics in a place where everyone can begin: questioning the world around us with a naive perspective, and trying to establish a consistent formal system for the answers that we find.

Ask yourself: what is space? What are things around me made out of? Is everything made out of something else? How big or how small can things get? Why is there change in the universe? What is time? And more importantly, how can we describe our answers so that they all relate to each other?

All these questions have their own place in the history of science, with various different answers and interpretations. It's well important to always have your own unique understanding of the world around you, but equally as important is to acknowledge that the people around us express similar understanding. This can only really be experienced when one questions deeply and shares their answers with those around them.

Luckily, many individuals have dedicated their lives to exploring these thoughts for us, leaving us with the details of their findings. We focus at the beginning of the 20th century. Science, after the agreement of many thousands different individuals throughout history and cultures, managed to create a formal system in explaining the world around us. The classical world, is what scientists call it, is the world that exists above the size of the atom and under the speed of light. This is the world that we live in day to day, the world that for centuries physics has been able to almost entirely explain. But once we leave the classical world, we find a world where nothing seems to be consistent. There are rules in this classical world, such like that everything exists in only one place at one time, that time cannot travel backwards, and that immediate things happen because of their immediately nearby surroundings.

But in quantum mechanics, the data tells us that the quantum world, the world of extreme energies at scales much smaller than atoms, is much different than the classical. All of the classical laws are broken down; there are some seemingly "reversal" of time phenomena in quantum interactions; in quantum entanglement, two states of a particle become "entangled" even if they are across the universe; and the rules of the mathematics and even logic become different. Instead of a bit system, for example, where logically the expression is "if A then B", you have a qubit system, where the expression becomes "if A then perhaps B to infinity." There is no exact consistency or certainty in the mechanics of quantum systems, only likely probabilities. With mathematical knowledge of how these quantum systems behave, using ideas called unitarity, quantization, conjugation, normalization, and others, science has allowed for the usage of quantum systems in some if the most efficient technologies in the modern world.

However, around the precise and rigorous mathematics and between the sea of possibilities is where the space opens for interpretation of the deepest foundations for our universe.

We now come to the philosophy, and ultimately, the implications of what such theories mean. Early quantum physicists were also philosophers. Anyone well versed in philosophy can recognize the principles of solipsism, epistemology, and existentialism. However, some of the more notable quantum physicists also had an interest in Far East philosophy, particularly from Vedic India. Some argue that this personal interest of theirs helped shape their experience with science and mathematics. Afterall, both quantum theories and Vedic philosophy speak of a seperate world, whose rules help influence or own despite the strange parallels between the worlds. Today, if there are traces of this Far-East philosophy, then they have surely found their roots in what academic quantum physicists call "quantum woo". Many have become famous at talking about things like quantum spirituality and quantum consciousness, which many have surely noticed is more philosophy than rigorous, hard, experimental science.

However, these surprisingly abstract and holistic perspectives aren't quite unlike the early attempts by quantum physicists themselves, where there was no foundation or work of generations before to give guidance and insight on where to travel next. Sure, after decades of research, quantum mechanics has been able to understand why the classical world works the way it does, and has even been able to create technology not otherwise possible, like the touchscreens on our phones and the pointing lazers we use to have fun. It's made it possible to understand atoms and how they join together to create more complicated structures to form either the foods that we eat or the materials found deep in the Earth's core. Quantum mechanics even gives some insight on the study of life, like how plants convert energy from the sun into food for its survival.
But at the end of the day, quantum mechanics is actually not the most complicated thing out there; rather, it's how the advancement of new science and the wondrous ambiguity that it leaves us humans seems to keep us at an ever-constant distance from understanding the universe. And in this way, quantum mechanics truly is no less relatable than questioning the smallest and most mundane activities of life.