Lesson 1 A Little Bit About This On-line Text
Quarks, Spacetime, and the Big Bang is a book designed to accompany a general education course of the same name that I’ve taught at Michigan State University for a number of years. Why? Well, there’s a story there.
The North American approach to university education is nearly unique in the world. Citizen-students come to college in order to become proficient in a focused few areas of study (your “major”) but are also broadly educated in many other areas (“general education”). So an English major would dive deeply into literature but also take courses in physics, astronomy, chemistry, biology, geology, history, anthropology, psychology, etc. Likewise a physics major would study physics and mathematics, but also biology, literature, psychology, and so on. Every U.S. campus manages this deep-plus-broad approach to higher education in its own way.
Creating courses for non-specialists in the sciences is especially challenging, but it’s important because many of society’s big problems are scientific at their roots: Climate change. Energy production. Evolution and big bang in schools. Nuclear power. Nuclear proliferation. NASA. NIH. Vaccination. Pandemics. Weather. Health effects (or not) of common radiation sources. Peer review. Basic versus applied research. Should I go on?
An informed citizen needs to understand some scientific facts, while also appreciating how science is done: all too often, controversy swirls as much around what is or isn’t “science” as it does to the details. How best to do this in physics?
There are many physics courses for non-science college students. The traditional course is often informally called “Physics for Poets,” which is a conceptual (less mathematical) version of the otherwise full-physics curriculum taught to science and engineering students. But there are other paths which teach physics by shining a light on particularly interesting topics in accessible presentations.
1.1 What Quarks, Spacetime, and the Big Bang Isn’t
This book is not a comprehensive survey of all of physics. You’ll not be expected to solve many of the standard “physics class” problems—Quarks, Spacetime, and the Big Bang is mostly conceptual. Many topics which would be in a conventional course are not covered here. For example, there is no chapter on thermodynamics, nor rotational dynamics, nor energy production, or climate. Motion and forces are only considered for one-dimensional situations and only in enough detail in order to appreciate Einstein’s Theory of Special Relativity. Electricity and magnetism are covered in a descriptive way, with only a few quantitative examples. “How things work” is sometimes touched, but less so than from the usual survey course.
We cut a strategic path through “classical” areas of physics in order to accumulate the concepts, quantities, and vocabulary that would apply to a conceptual appreciation of relativity and quantum mechanics, both of which are the jumping-off points to our two main topics.
Wait. Einstein’s theory? Quantum Mechanics?
Glad you asked. Sure. You’ll be surprised at how much relativity and quantum mechanics we can do with very simple mathematics. It will be challenging for you in the same way that’s it’s challenging for us – it kind of stresses your common sense. But not your mathematical skills.
1.2 What Quarks, Spacetime, and the Big Bang Is
My aim is to help you appreciate two of the more exciting “fundamental” topics in physics: particle physics and cosmology. You’ll come to appreciate our current understanding of how our universe began and what open questions continue to motivate thousands of us around the world. Once we’ve passed through a gentle introduction to motion, collisions, electricity, and magnetism, the light-algebraic approach evolves into a more conceptual narrative where we tackle modern-day topics.
1.3 The Great Scientist Theory
I’ll bet that you think of physics as strange symbols and dry prose memorialized between the covers of big books and obscure journals. There are books! But at its most basic: physics is about people. Every once in a while, someone does something amazing – they reinterpret some phenomenon differently or have an idea that nobody else has. Everyone I work with is smart. But there have been some scary-smart people in the history of science and I’d like for you to meet many of them. Not only because their lives and discoveries are great stories, but I think the people side of things lubricates the details.
I’ve found that the physics content will stay in your mind because you’ll easily associate it with someone’s life story. So rather than stick a little scientific biography in a sidebar like many books, I’ve built all of Quarks, Spacetime, and the Big Bang around people. Each lesson begins with: “A Little Bit of X” where X is the host of that lesson’s topic. Sometimes your host will be someone you’ve heard of (“A Little Bit of Einstein,” “A Little Bit of Newton,” and so on) or sometimes your host will be someone you don’t recognize (“A Little Bit of Huygens,” “A Little Bit of Kepler,” “A Little Bit of Dirac,” and so on). Once you’re acquainted, the flow of that lesson will follow each host as they change physics forever.
By the way, there are thousands of productive scientists whom I don’t single out with “A Little Bit of …Smith.” Smith might have been a productive scientist, but she’s like the vast majority of us. We’re good at our jobs, but we don’t build worlds.
No, here we’re going to highlight those Amazing People. Heroes to whom my friends and I are professionally, and even emotionally, connected. We talk about them all the time at lunch. Our conferences have special sessions devoted to them.
Most historians dislike what’s sometimes called the Great Man Theory which aims to explain major events in world history through the actions of a single person. The 19th century GMT typically includes a narrative about this person as born with superior qualities and destined for the great (or evil) outcomes that he would induce — we’ve all heard these stories. Sometimes the history of science is presented this way and, predictably, many professional historians don’t like this either.
Let me use an analogy for my own Great Scientist Theory. Play Ball!
1.4 How I Think About You and Me
This is a picture from July 13th during the 1965 Major League Baseball All Star game in Metropolitan Stadium in Bloomington, Minnesota. I like this image as an analogy to how I think of scientists and…you.
Figure 1.1: From the cheap seats in Metropolitan Stadium.
1.4.1 The Greatest Ballplayers
At that time, MLB had 500 professional players and this game was notable because it featured 19 future Hall of Famers. That means that 34 professionals on the field that day were not going into the history books, nor were the other 447 who weren’t invited. Those 19 were pretty special athletes.
I guarantee you that when they played, their colleagues were often in awe. The 481 guys superbly talented enough to make their living by playing a professional sport, but not going to The Hallof Fame, know that among them there are players who are special. (And for the rest of their lives, they talked about what it was like to play with Henry Aaron, Mickey Mantle, and the others.) Athletes are not ashamed to celebrate their super-human colleagues. Stories will be told, legends will be created, and songs will be sung about those guys — because they were great.
1.4.2 The Greatest Scientists
Just like it would be impossible to write the history of baseball without special reference to the greatest players of all, so too it’s impossible to write the story of science without reference to the greatest among us. Just like the regular professional athletes, those of us who make our living as professional scientists celebrate our heroes: the ones who saw the world differently from everyone else. Those of us who’ve been privileged to actually work with Nobel Laureates know this to be the case.
Perhaps you’re not surprised at my impatience with the “mad scientist” TV image. Marty McFly’s Doc Brown is my least favorite example of a scientist.
So, in Quarks, Spacetime, and the Big Bang, I’m all-in with the Great Scientist Theory and you’ll get to meet many of the men and women who changed the world with their imaginations and technical skills.
Wait. Baseball players from 1965??
Glad you asked. Yup. I just explained why, but wait, you’re also at this game.
1.4.3 The Greatest Spectators
If you’ve never played baseball or softball, attending a baseball game can be a little overwhelming. The rules can seem strange and you’re probably puzzled by the seriousness of many of the spectators around you. You’ll even see many of them with pencils and scorecards and taking part in earnest discussions about some of the events that happen on the field. They clearly appreciate pitching, fielding, and hitting; strategies; good and bad play; and importantly, fundamental skills. They grasp the game differently from others.
If you’ve never taken a physics course or read one of the hundreds of terrific books written to help non-specialists appreciate both historical and modern ideas and discoveries — you’re perhaps like that spectator over on the third base side, about 15 rows up. She’s attending her first game and she’s a little puzzled about what just happened on the field.
I view my job in Quarks, Spacetime, and the Big Bang as taking you from being the confused fan, to someone who won’t play the game professionally but by the time we’re done will be able to judge what’s good, what’s bad, and what’s amazing about both the scientists not headed for the history books as well as the ones who will find themselves immortalized with universal admiration.
1.5 How Deep Do We Go?
So, this is not the place for you to become a scientist. But it is a place to do some work and I will both be gentle and clear about what I hope you’ll take away.
Every lesson will itemize three categories of goals that I hope you’ll achieve. After completing each lesson, I hope you will know some things well and have a feeling for others. I call these levels of achievement Understanding, Appreciating, and Familiarizing.
Understanding. This will often mean demonstrating some facility with a calculation or reading a graph in order to acquire insight. It probably means that you’ve followed a simple mathematical argument interactively. For example to Understand a recipe means that you’ve prepared a meal using it. It doesn’t mean that you created the recipe.
Appreciating. This is less quantitative and less demanding than Understanding. To Appreciate a recipe you would realize that to sweeten it you’d add sugar, but not be able to predict exactly how much to add. You’d need an expert, but you’d know who to ask and what to request.
Familiarizing. This is a fly-by of some story or feature of a bit of our physics story. To be Familiar means that you know to go to Mr Google for information, because you can’t remember the details. Continuing with the food analogy, you might be Familiar with the idea that recipes for chocolate cookies exist, but you’d need the web or a cookbook in order to Appreciate or Understand one.
1.6 Let’s Go!
I’m an experimental particle physicist and I’ve been teaching physics to physics majors and especially non-science students for four decades and I have fun doing it. I’m lucky enough to be continuously supported by you and your families through grants from The National Science Foundation and the US Department of Energy for my research for 45 years and I’m grateful. In some ways, this book and course are in partial repayment for that support. Thanks.
I’ve never met anyone who didn’t share my curiosity in wanting to know how the universe works. Even after a lifetime immersed in these matters daily, I’m in awe at how beautiful it all is and how lucky we are to know as much as we do. I enjoy talking about it and teaching some of the details.
You can find more about me at about me and you’ll get to know me a little as I tell you stories in the lessons that follow.
I’m not stuffy. I’ve tried to write here like I teach, which is informally and without pretense. I’m deadly serious about the science and passionate about the subject matter. But I also like to have fun and I’ll make you smile every once in a while as we work to grasp complex ideas. Stay with me, and you’ll be able to explain Special Relativity at parties just like I can!
Wait. That may not be a selling point.