Everyone Is Now Dumber for Having Listened to You

Short post today, but I wanted to share this. A friend and fellow physics grad student just shared this video on Facebook. This is quite possibly the most wrong statements (both in number and in wrongness) in the shortest span of time that I’ve ever seen. Naturally, her lecture is on homeopathy, the most insane, anti-science, anti-thinking idea ever conceived.

This is one of those rare, special cases where the famous Billy Madison quote is literally true. Every single statement she makes is not only wrong, but probably the most wrong it could be. She even gets Stephen Hawking’s name wrong! Well… there is one statement, and only one, that she makes which is actually true (besides “hello,” etc.). Ready for it?

“We have light receivers [eyes], and we have ears.”

That’s it. That’s the only aspect of physics, biology or chemistry that she seems to have even the most rudimentary grasp of. But, again, she’s a “doctor” of homeopathy, so she gave up on things like science and facts long ago.

Anyway, ranting is fun, but it’s time for me to shut up and share the video. Be warned, this will probably hurt your brain.

P.S. In the process of writing this post, I discovered that this video first made the rounds about five years ago. And apparently “Dr.” Werner got really angry about it going public. I still think it’s worth sharing again. It’s good to remind ourselves just how wrong we can get things when we don’t bother to really try to understand science and just interpret it to say what we want. And it’s also really funny.

If the Earth is Getting Warmer, Why is it so Cold?

Well, we just had our first real snow of the season here in Lexington, so I thought this would be the perfect time to share this. This is a talk that was given in the physics department about a month ago by Dr. Jennifer Francis of the Rutgers University Institute of Marine and Coastal Sciences.

Dr. Francis explains how global warming, specifically the melting of arctic sea ice, can lead to more severe winters for Kentucky and the Midwest (as well as other forms of extreme weather).

I found her talk to be very clear and informative. Unfortunately, the recording is rather poor. It starts a few slides in, and the camera that’s supposed to automatically track her doesn’t work, so you never see her. (That’s the shot of the desk in the bottom right.) But I still think it’s worth the time to watch it.

To summarize: the rapid increase in average temperature over the last century has led to an increase in the melting of arctic sea ice. The arctic ice sheet has been melting enough in the last decade or so to expose large areas of the Arctic Ocean. This leads to more rapid heating (liquid water heats much more quickly than ice) which causes the arctic to warm much faster than the rest of the planet.

This is a problem because the air currents called jet streams are created by the temperature difference between the lower latitudes and the arctic. The jet streams are the main component of the weather patterns in the northern middle latitudes (viz. North America). As the arctic gets warmer, the jet streams get wavier and more chaotic. This causes more extreme and more persistent weather patterns like the California drought and the extra cold winter we had last year.

Dr. Francis goes into much more detail about the process, including how she and her collaborators tested this theory.

Interstellar and the Sci-Fi Uncanny Valley

Preface

I know I was in the middle of writing about other stuff, but I just saw the movie Interstellar last night, and I wanted to share this thought. I’ll get back to atoms and my research soon.

The Uncanny Valley

R2-D2 is cute, Wall-E is adorable and Joel and Ellie from The Last of Us seem almost real. But the conductor from Polar Express is kind of creepy and the robots in this video are some of the creepiest things you’ll ever see. (Seriously, don’t watch that video unless you’re prepared to get creeped the hell out.)

The uncanny valley for robots and puppets. A bunraku puppet, by the way, is sort of a Japanese marionette, except even creepier.

This is the uncanny valley. If a simulated character (robot, CG, puppet or otherwise) is only vaguely humanoid, then we will pick up on the human/animal like traits and relate to it. If it’s a very good simulation, then we can relate to it as if it were a real person. But if it’s most of the way there, but not quite, it makes our skin crawl. There’s been a lot of thought put into the causes of the uncanny valley and how to avoid it. I won’t get into all of that, but I do think it has a lot to do with consistency. If some traits look very real, but others are noticeably off, that is more disturbing than if it were a consistently bad simulation.

The Sci-Fi Uncanny Valley

I have a theory that a similar uncanny valley exists in science fiction, especially for sci-fi fans like me who are also scientists. If a movie or series plays fast and loose with the science, using the word “science” to refer to what is basically magic, it can be hugely entertaining. Doctor Who is a great example of this, as are most superhero movies. It would be near the left side of the sci-fi version of the graph above. Most of the incarnations of Star Trek would be near the first peak. They show enough scientific knowledge to really excite the imagination, but hand-wave the details enough to not be jarring when they just pull something out of their ass. Up in the top right corner of the CG/robotics graph is “actual human.” The corresponding point on the sci-fi graph would be “actual science,” documentaries, non-fiction books and such.

So what’s down in the bottom of the sci-fi uncanny valley? Well, until recently I would have put Armageddon and The Core down there, but really those are somewhere on the downward slope to the left of the bottom. As I’m sure you’ve guessed, I would put Interstellar right there at the bottom of the valley. Don’t get me wrong, I thought it was a really well made and entertaining movie, and I would recommend it to most people. I love the central message of the movie: that if we are to survive and grow as a species, we must continue to explore space. But the movie is so careful to get certain details right, that whenever it makes a mistake it is screamingly obvious. Even worse, the movie is so damn inconsistent about the details.

The specific mistakes and inconsistencies are far too numerous to cover in a single post. Maybe I’ll come back to them at some point in the future. Although before I tear this movie apart, I may want to attack the worst fake science fake documentary ever made: What the Bleep Do We Know!?

Edit: By the way, if there are any movies, books or TV shows that you think are particularly good examples of the sci-fi uncanny valley (or other points on the graph), please share.

Atoms, Part 1: The shape of an atom

Matter is made of atoms. This fact is familiar to everyone. But the basic structure and behavior of atoms is so fundamental to understanding modern physics, that I want to take some time to review it. It’s so important, in fact, that Richard Feynman began his famous lecture series by saying:

If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generations of creatures, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis (or the atomic fact, or whatever you wish to call it) that all things are made of atoms—little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another.

The atomic hypothesis–that matter cannot be infinitely divided–was first proposed around 2500 years ago, but at that time it was pure speculation, and for most of those 2500 years, it wasn’t a very popular idea. Our modern understanding of the structure of atoms was mostly developed around the beginning of the 20th century, with some parts of the theory developed as recently as the 1960s. If you want to know more about this history, the Wikipedia article on atomic theory is a good starting point1. For now, I want to focus on our modern picture of the atom.

Atom is actually a misnomer. It comes from the Greek for “indivisible,” but atoms are actually made of smaller particles: protons, neutrons and electrons. One might naturally ask, “Are these particles made of even smaller particles?” For protons and neutrons the answer is “Yes!” They are made of quarks and gluons. This is the part of the atomic model that was developed in the 1960s, and physicists are still studying the dynamics of how, exactly, quarks and gluons interact within protons and neutrons. Electrons, on the other hand, are elementary. As far as we can tell, they are not made of any smaller particles. (The same is true for quarks and gluons.)

The atomic model most people are familiar with goes something like this: protons and neutrons are tightly bound together in the nucleus of an atom, with electrons orbiting the nucleus in much the same way that planets orbit the Sun. This is called the Bohr modeland it’s about a hundred years old. It is accurate in a lot of ways. Protons and neutrons are, indeed, bound together in the nucleus (by the strong nuclear force, or the strong force for short), and electrons surround the nucleus in orbitals. Electrons are bound in these orbitals by the attraction between the positively charged protons and the negatively charged electrons (neutrons have no electric charge).

However, these electron orbitals are basically nothing like planetary orbits. The Bohr model was only around for about a decade before physicists (including Niels Bohr himself) began to realize that it wasn’t quite right. But the Bohr model still persists as the popular image, (just try doing a Google image search for “atom”) probably because the more accurate model is a bit harder to visualize and explain.

The old Bohr model and the not quite as old electron cloud model. This image was shamelessly swiped from this website.

The modern picture is called the electron cloud model, although I prefer to think of it as the “electron bubble model.” Particles are usually pictured as little balls. This picture is almost, but not quite2, completely wrong. Instead, a free electron is “shaped like” a point (as far as we’ve been able to observe. They may actually be shaped like little strings, or something else.) But when it becomes bound to an atomic nucleus, the electron spreads out and become “shaped like” a bubble surrounding the nucleus3. I prefer the term “bubble” to the more commonly used “cloud” for two reasons. First, it makes it more clear that a single electron4 forms the entire bubble (rather than being a “gas” of a bunch of electrons). Second, the shapes of electron orbitals are very closely related to the ways that a sphere (or bubble) can vibrate.

The first several spherical harmonics. These illustrate both some of the vibrational modes of a bubble, and several of the shapes of electron orbitals.

The electron cloud is much, much bigger than the nucleus; about 100,000 times bigger. To get a sense of this scale, take an orange and go stand at the center of the New Circle Road loop around Lexington, KY5. (It turns out this is roughly at the Chemistry-Physics building on UK campus.) If an (average sized) atomic nucleus were the size of the orange, then an atomic orbital would be about the size of the New Circle Road loop.

How big are atoms themselves? Again let’s look at our orange. If we blew up the orange until it’s the size of the Earth (about 8,000 miles in diameter), then the atoms inside it would be about an inch in diameter. Our reference orange is made up of about 1025 atoms. In long form that’s 10,000,000,000,000,000,000,000,000 atoms or ten tera-tera-atoms.

So atoms are tiny, have a simple but bizarre structure, and make up (nearly) everything. Of course, if atoms make up all the matter we see, feel or otherwise interact with, there must be many different types of atoms. As you may already know (or at least suspect), this has something to do with the number of protons, neutrons and electrons in an atom. But let’s take a break for now. We will talk about that next time.


1I’d love to recommend a good book on the history of atomic theory. Unfortunately, I learned most of it from classes and textbooks, so I don’t know any good books about it (although I’m sure they’re out there).

2For composite particles, like protons, neutrons or entire atoms, the “little ball” picture is still somewhat reasonable.

3These point and bubble shapes are “fuzzed out” due to the uncertainty principle. This is where the term “electron cloud” comes from. And for any physicists reading this: yes, I’m hand-waving the whole topic of probability distributions for now.

4Because electrons have a property called spin, up to two electrons can occupy the same orbital (the same bubble shape) at a time. Spin is an entire topic in itself that I won’t get into right now.

5If you’re not in Lexington, any geographical feature with a diameter of about 5-6 miles will work.

So what’s your research on?

I’ve been asked several times by my family (especially my parents) to explain what my research is about. The short answer is that we’re measuring the rate of muon capture on deuterium. The problem is, that answer is meaningless to non-physicists. What’s a muon? What’s deuterium? And what does “capture” mean in this context? The extremely simplified answer I’ve been giving, “We’re shooting a beam of one particle into a gas of another particle to see how often they stick together,” isn’t much better.

The problem is, to give a good explanation of what we’re doing over in Switzerland, I have to explain some of the physics behind it first. This isn’t really a problem because I love talking about physics, but it does mean that the explanation will take a little while. I’ve been trying to get myself started writing about physics for the last few years anyway, so I figured I’d write up the explanation as a sort of blog.

Following Kurt Vonnegut’s rules 1 and 5, I’m going to try to stick to just the physics necessary to understand my research. I have a bit of a bad habit of rambling off topic when talking about physics. But also following Vonnegut’s rule 7, I’m going to write this towards my parents who are about as non-scientist as you can get, especially my mom (no offense, Mom. I love you!). Here’s the outline I’m planning for now. This will be very likely to change as I get going.

  • Atoms
  • Atomic nuclei and isotopes (possibly in the same post as atoms)
  • Nuclear reactions: capture, decay, fusion, fission, radiation, etc.
  • Muons and possibly some other elementary particles
  • Muon catalyzed fusion and solar fusion
  • The MuSun experiment (our experiment)

For now I’m going to try to post about once a week, probably on Fridays, but that is also subject to change. Please ask lots of questions and post lots of comments. Let me know if things don’t make sense (and if they do).