Introduction

• Where the standard model falls short
• A brief peek at relativity
• A few possible schemes for quantum gravity
• The problem of testability

It seems that physicists are never satisfied. Their goal is no less than a complete understanding of the universe—past, present, and future. Quantum physics has produced great progress toward this goal, and the standard model summarizes that progress and our current state of knowledge very well. But it certainly does not give us a complete picture.

We start the looking more deeply into where the standard model falls short. By examining the shortcomings, we hope to get some idea of how to fill in those gaps, and eventually achieve an even more complete understanding of nature. Incorporating gravity into a quantum framework is a major part of the problem. So we will look at a couple of ways that theoretical physicists are trying to tackle this problem.

We will be taking you to the edge of what is known in physics. This will naturally lead us to question what can be known, and whether our lofty goal of complete understanding is, in fact, achievable. We don’t know if the next revolution in physics is just around the corner, if we will continue to make slow progress within the existing framework, or if progress will come to a complete halt. Only time will tell.