0 The Guide to the Guide

The Philosophy Behind the Guide

This guide is for those brave souls who have a deep yearning to climb the cliff of modern physics. We intend the guide to be accessible to people at nearly any level of learning; giving a broad overview of the topics which are essential for engaging in a productive dialogue with the universe and its laws. In a typical undergraduate physics education, there is a very specific ordering in which topics are presented. Such an ordering is useful in so far as it provides students with a clear route up the cliff. Part of the art of climbing, however, is learning how to find one's own route up the cliff face, a skill not often learned in college. Indeed, finding new paths to familiar ideas is the skill which separates the good physicists from the mediocre. When extended, this skill allows one to free-climbing to new heights on the cliff face, the hallmark of an excellent physicist.

Here, we only intended to show you the cliff face while suggesting an admittedly vague path up the wall; it is nearly impossible to climb that which has not been seen. To this end, we will be following Roger Penrose's book The Road to Reality, whose chosen ordering of topics is sufficiently unorthodox as to preclude any attempts to skip the important step of learning to climb. Furthermore, it is the only book that I am aware of that contains nearly all the necessary concepts to deliver a student to the edge of that which is known. Due to the incredible breadth of subjects covered in the book, each chapter skips over a swath of ideas and does not fully expand upon the ideas presented. This collection of resources is intended to fill in these gaps and give direction to any sufficiently motivated autodidact staring longingly at the clouds. We call this method guided self-learning.

How to Use the Guide

First of all, let it be known that while the book is (necessarily) ordered linearly, you are by no means constrained to this ordering. Let your curiosity run wild! That being said, many of us like the structure that book provides, which each chapter coming after the next, so if you would like to read chapter by chapter, great, if you would like to skip around to what sounds interesting also great, but do not be surprised in either case if you run into many things that do not make sense upon a first read. This is where the guide comes in.

We have divided the guide into six sections:

• Community Explanations
  • These are summaries of the key points in the chapter written by our community contributors. A quick way to review the contents of a chapter or just read an additional take on a given topic.
• Preliminaries
  • Resources covering concepts that we recommend you have a firm grasp on before going into a chapter. Knowledge of concepts covered in previous chapters is assumed.
• Essential
  • Resources which we strongly believe will solidify the most important concepts presented within the chapter.
• Recommended
  • Resources which should be reviewed if a given concept in the chapter just didn't quite click.
• Further Reading
  • Resources, often textbooks, which constitute the next steps to understanding the topics presented in the chapter at a deeper level.
• Art

Common Failure Modes

While these guides are intended to be accessible, make no mistake: learning physics is extremely challenging. If you commit sufficiently to this journey, it is liable to become one of the most difficult undertakings in your life, it is also likely to be one of the most rewarding. Below are two failure modes that you should be aware of:

1. Thinking that you understand something when you don't: Words like energy, quantum, and electromagnetic field are bandied about casually in conversation, but most people, if challenged, would not truly know what these things mean. It is absolutely fine to not understand something, but we are all quite good at convincing ourselves that we understand something that we don not. We are all excellent self-deceivers. To prevent this problem, it is important that you challenge your understanding with practice problems covering any topics that you believe that you understand to confirm that this is true. This will slow you down in the short term, but over the long term, it will prevent you from wasting massive amounts of time having to unlearn your mistakes. Remember, slow is fast and fast is slow.
2. Giving Up and Burning Out: Physics is brutally unforgiving. If you're wrong, you're wrong, and you're going to be wrong a lot before you start being right. For this reason, it is important to remember that our current knowledge about physics and math has been built up by some of the most brilliant people in the world over the course of thousands of years. It is bound to take a substantial amount of time to learn even a fraction of what has been discovered. You are not "stupid" if something doesn't make sense to you over the course of days, weeks, months, or even years. Confusion is an experience that unites all people who have ever studied physics; confusion is the indicator that you still have room to grow! The trick is to dive deep enough into the subject that some things are unfamiliar, but not so far that everything is unfamiliar. This positions you to learn new things without battering your confidence to the extent that you burn out and give up.