On Writing Novels (and Being Fun at Parties)

On Writing Novels (and Being Fun at Parties)

Physicists are not much fun at parties. Conversations with us about the universe usually follow a common pattern; you’ll mention or discuss some creative and interesting idea about reality like “cold stars” or faster-than-light travel, and we’ll coldly shut the idea down with some unnecessarily verbose, almost pedantic technobabble. In this entry, I’ll try to explain why our consistent stuffiness is an acquired trait of the business, and how being boring with our ideas prevents us from conceptually destroying billions of galaxies.

Say somebody asks you to write the next novel starring Hero X, the star of a multi-decade science-fiction franchise. Enthused, you proceed to write about his thrilling adventures in the Crab Nebula, only for your editor to tell you that the Crab Nebula got blown up in a comic book spinoff starring Hero X’s dog companion. You then try to write a story about stopping a cryogenically preserved Soviet cyborg, until your editor lets you know that the Soviet Union never existed because a side character in Hero X’s time travel novel mentioned Tajikistan in 1934. Eventually, you decide to write a quaint book about Hero X facing his inner demons during a beach retreat in the Maldives; that is, until the editor mentions that the creator of Hero X wrote a letter to a fan stating that Hero X is terrified of the ocean and that the Maldives were teleported onto Deimos in an audio drama from the 1980s. At this point, you would probably strangle your editor and start your own franchise unless you were insane (or a physicist).

Hero X 2

See, devising interesting and creative ideas in physics that stick is difficult in exactly the same way as writing a Hero X novel; any single addition to our catalogue of creation interferes with everything else in monumental ways. Inventing anything that goes even slightly faster than the speed of light means you can now time travel into the past. Making a single magnet with only one pole causes electric charge everywhere in the universe to be restricted to specific values (this may actually be true). Creating a machine that harvests the tiniest amount of energy out of nowhere means that no coherent laws of physics can exist, as I explained in my previous post. Even an idea that seems harmless, like assuming that there is some inconceivably small minimum distance in the universe, puts the “relativity” part of general/special relativity straight in the shredder. Even though these examples would take far too long to elaborate on in this single entry, I’ll discuss in relative detail another creative idea physicists had some years back with similarly unexpected consequences.

Here’s a thought; say that there’s some large, isolated patches of the universe made up purely of antimatter, with antigalaxies and antistars and antiplanets full of antipeople just like you and me. Doesn’t seem like a problem at first glance, right? Antimatter is just matter with the electric charges (and some other things) flipped backwards, and that doesn’t really stop you from generating all the elements needed to make anti-you. In fact, the laws of physics don’t seem to indicate any difference between matter and antimatter other than that little inversion quirk, so why shouldn’t there be just as much antimatter floating around somewhere?

The first problem with this idea is that the “borders” of these antimatter domains would often come into contact with our own normal matter domains; and since matter and antimatter don’t like each other very much, these collisions would utterly delete everything in their immediate vicinity from existence (normal and anti), triggering bursts of intensely powerful light that would serve as the single brightest events in the known universe. Given that quite a few experiments have been looking for these huge flashes to no avail (and trust me, we’d see them), this little attempt at creativity of ours would seem to be a bust.

Another, even bigger, problem; if the universe was actually made up of equal parts matter and antimatter, there’s no reason why both kinds of matter wouldn’t have destroyed each other completely right after the Big Bang, when the universe was the size of a walnut! We’d have been left with an empty universe, filled only with faint, dead light. Consequently, we are forced to conclude that the laws of physics discriminate in some tiny way between matter and antimatter, and are left to figure out why this caused our universe to be composed of (almost) exclusively matter. Good luck, theorists!

Strange Science 2

This should give you a bit of insight as to why the last two major theoretical advances in physics, quantum mechanics and relativity, have been such complete retcons of our previous laws of physics instead of just additions “tacked on” to the old ones. Imagine how conceptually crowded physics was back at the start of the 20th century that the only way scientists could explain (without contradictions) why lava glows red was by developing a theory that lets everything have the probability to exist almost everywhere in the universe at the same time. This is like getting away with your Hero X beach retreat novel by writing a chapter where an intergalactic version of the CIA finds an exact clone of the Earth (Maldives and all) in the Andromeda Galaxy, controlled by aliens that have replaced all the water with a virtually identical synthetic compound. Hell, I’d read that!

CIA 2

I’ll finish this entry by mentioning one of the very few ideas in physics that is both simple and non-disruptive; dark matter. To make a long story short, a scientist in the 70’s realized that for galaxies to spin the way they do, either 1) Einstein’s theory of gravity is fundamentally wrong or 2) there’s a bunch of invisible stuff we haven’t discovered yet floating around in every galaxy. Ambitious and creative theorists have jumped at the chance to rewrite the laws of gravity to account for this, but the above examples may clue you in as to why these theories have not been largely successful; rewriting even a small piece of Einstein’s equations leaves you unable to explain why stars last longer than 2 weeks or why light bends around stars the way it does. On the other hand, if you just assumed that there’s a specific type of particle in existence zooming around that’s invisible to our telescopes, then that’s all there is to it! No need to rewrite every known principle in the laws of physics. All that’s left is to actually find the damn thing, which is (of course) hilariously difficult; but there are dozens of scientific collaborations filled with people much smarter than me working on it. I should know; I used to work for one of them! Wish them luck, and don’t be too hard on your physicist friend when he tells you that black holes being wormholes to another part of the universe would violate conservation of energy.

On the Behavior of Cats

On the Behavior of Cats

In this entry, I’m going to try and show you what might be the most fundamental concept in all of physics by talking about some of the universe’s most mysterious objects: cats.

Whether it’s the perpetual obsession with sleeping in boxes, the constant desire to go outside and then immediately come back inside, or their fascination for canned spaghetti (this may be just my cats), the mind of a feline would appear to be an utterly undecipherable thing. But every cat owner has attempted to understand its cat’s behavior in some manner, and I’ll try to explain this process to those who have never owned a cat.*

*Cat people will agree that it’s technically the cat that owns you.

In attempting to figure out my cat’s strange culinary preferences (which appear to include everything from Swiss cheese to guava paste), I decided to leave some broccoli out on a plate one day and see if he’d take a bite. At the end of the day, my cat decided to leave the plate of broccoli untouched; rejecting them for the roasted chicken leg I was holding in my hand at the time, and leading me to conclude that my cat indeed does not like eating his greens.

To present the above in a more abstract way, I had attempted to make a guess at some aspect of my cat’s behavior, which can be described by a statement like “My cat does not like eating broccoli”. Now, since the nature of a cat is inscrutable, I have no way of fundamentally knowing what my cat truly likes eating; but I can attempt to associate my prediction of my cat’s food preferences with some measurable constant quantity like “the amount of broccoli on my cat’s plate”. If the amount of broccoli on the plate didn’t change after a day or two, then I’d reason that my cat didn’t eat any because he tasted it and didn’t like it. If instead I see that the amount of broccoli drops by some amount every day, I might say something along the lines of “my cat enjoys eating broccoli every day”. Simple!

Cat Example 1

Although strange at first glance, the association of a behavioral prediction/statement with some constant quantity is something we do every day. You may predict your father likes steak because he visits a local steakhouse a regular amount of times a month, for example; you may also observe that a friend takes a constant type and amount of pills every week and conjecture that he suffers from a chronic medical condition. Both behavioral statements, “my father likes eating steak” & “my friend has a chronic condition”, are fundamentally tied to some constant quantity that we can observe (“the amount of times my father visits a steakhouse a month” & “the amount/type of pills my friend takes a week” respectively).

Now, I can take it a little bit further philosophically and (cue the Inception horn) make a statement about my statements of what my cat’s behavior is like. An obvious one is to assume that my statements are always going to be right; that is to say, that a statement I make now will hold for all of time. That does not mean that my cat’s behavior can’t change over time; it just means that I have to describe that change in my statement, which itself cannot change over time. One may argue fairly easily, from a philosophical perspective, that this is a requirement in order for the statements to be correct or consistent. But the point is that this meta-statement about the “correctness” of my statements is a statement in and of itself.

Cat Example 2With all of this in mind, consider that a theoretical physicist’s job is to devise a series of statements/predictions about the behavior of everything in the universe; these being what we call “the laws of physics”. All of these laws can be judged to be “consistent” by stating that even though things in the universe may change over time, the laws of physics themselves shouldn’t change over time. Nothing controversial about that!

But what is absolutely stunning is that a very smart mathematician realized that this statement about the consistency of the laws of physics is also associated with a measurable constant quantity just like in my cat’s example! And in fact, this mysterious conserved quantity tied to the consistency of our laws of physics is something called energy. The whole point of this preamble was to get you to believe me when I state what might be the most fundamental principle in all of physics:

Conservation of energy is the consequence of unchanging laws of physics.

Consider what would happen in a universe where the laws of physics did change over time. I’d perform an experiment today and get some result; then I’d do the same experiment the next day and see something completely different! In fact, it would become completely impossible for science to exist at all since I wouldn’t be able to make any lasting conclusions based on my experimental observations. In this alternate reality, we’d have no guarantee that we wouldn’t suddenly fly out of our office windows, transform into polar bears, or collectively develop a sharp hatred for people who wear lime-green sandals. The entire concept of engineering goes into the gutter since buildings could just spontaneously transform into VHS cassettes of The Sandlot. Our existences would be a chaotic nightmare; our unknowable universe would just be one big metaphorical cat. Thanks, science!

For another fun fact, that very same mathematician I mentioned above went on to state that if the laws of physics are consistent across all of space as well as time, another conserved quantity shows up called momentum. Regardless of whatever definition of energy and momentum you may have been taught in high school, their true definitions are “the things conserved when the laws of physics are consistent in time and space (respectively)”. Now you know the real reason why your teachers kept mentioning those two things over and over!

Cat Example 3

I’ll finish off this post by saying that scientists have a funny term for these kinds of meta-statements about the laws of physics, and that many people dedicate their careers to proving or disproving these by performing experiments on the quantities associated with them. In fact, a very smart physicist discovered through such experiments that a meta-statement we intuitively thought was correct (“left and right are relative concepts in the laws of physics”) was actually completely wrong! Who knows; perhaps our universe is more cat-like than we thought.

On Stuff & Things

Everything in the universe can be said to belong in one of two different categories: stuff and things. Now, stuff and things are very different, and I’ll do my best to explain why below (and how the difference between them leads to the state of our universe as we know it).

Stuff

Stuff is, well, stuff. If you get some stuff and you put it on some other stuff, you just have more stuff. Boom! That’s that for now; there’s nothing else to it.

Things

Things are a little bit more complicated, but not by a lot. See, things are things, and if you try to put one thing where another thing is, you obviously can’t because they’re two different things. Simple enough.

When you were a child, this was explained in chemistry class (probably while you were sleeping) and in time-travel fiction (while you should have been studying for chemistry) using the following common-sense rule: No two things can occupy the same space at the same time.

But what’s actually pretty funny is that the “real” version of this is much simpler in principle:

No two things can be the same thing.

That’s it! It’s obvious; if two things were the same thing, then why would they be two things? They’d just be one thing, and then all of that same kind of thing would just be one big collective thing, and that would just be stuff. Capisce? Here’s a simple (read: made in Paint) visual comparison to help solidify what I mean.

Stuff_and_Things

With this in mind, it’s time to move away from the world of philosophical abstraction and actually mention examples of stuff and things in our universe.

Electrons & Atomic Structure (or Things on Things)

At the elementary level, practically everything is a thing; electrons, protons, neutrons, and everything made out of them (which is essentially, well, everything).

What’s actually very interesting about things is that the simple, essentially philosophical statement I made in the previous section about thingness is directly responsible for the existence of chemistry as we know it. I’ll show how & why below, but first I need to explain what makes an electron its own thing.

The first thing we need to know is that a single electron doesn’t exist as some tiny ball, but as a probability cloud with some specific shape; this is why it was important to generalize our common-sense statement about things not being in the same place & time since, technically, every electron exists practically everywhere in the universe at the same time. So now, that property of the electron we’d call its “location” can be replaced by a property we’ll call “cloud shape” or shape.

The other property that makes a single electron “its own thing” (that’s relevant to us) is a property called spin. Spin is tricky (it deserves its own post), but all you need to know is that it’s a property an electron has and that there are two possible values of it. In fact, if electrons all had name-tags that said either Harry or Bob instead of having spin, chemistry as we know it (sort of) would still exist. Go ahead, name them!* I’ll take the approach of painting a Harry electron blue and a Bob electron red in my illustrations, and say that our electrons now have names instead of spin.

*Just don’t feed them or you’ll have to absorb them.

The whole reason I bring these properties up is to explain why our atoms look the way they do. See, thanks to their names, electrons can indeed exist in the same place at the same time (a.k.a. have the same shape) as long as they have different names; because that means they’re still different things!

With that out of the way, consider the following two atoms in two different universes, one in which electrons are things (our own) and one in which electrons are stuff. Here’s what hydrogen would look like:

Hydrogen

Nothing seems different there. The simplest (a.k.a. lowest-energy) shape an electron can have around the nucleus is just spherical, and both electrons here take that same shape. Here’s what lithium would look like:

LithiumNow we’re getting somewhere. Once both Harry & Bob electrons exist in that first shape in our atom, you can’t pile on another electron without it possessing a different shape because the extra electron would be identical to either Harry or Bob, and would therefore not be a different thing. This is why chemistry teachers say things like “The first electron shell holds 2 electrons”, and why the first row of the periodic table only has 2 elements. For lithium to form, what then winds up happening is that the extra electron would have to change its shape to get bound to the nucleus (with a little energy boost), and that’s exactly what the extra Harry electron in our lithium illustration does.

In contrast, stuffium-3 doesn’t need each electron to be individual things, and so allows all of them pile up indistinguishably in that lowest-energy sphere shape.

Now here’s what carbon would look like:

CarbonCompletely different! The trend is evident; our electron-thing atoms seem to obtain spatial structure when we pile up electrons, while different elements of stuffium look exactly the same since we can just pile up electrons indefinitely in that lower-energy sphere shape. In carbon, we’ve already filled out that second spherical shape we saw in lithium with another Harry and Bob, and so we see the two extra Harrys forced to take on some funky non-spherical shapes. (Two ovals on the same axis are the same electron). Note that you can always distinctly identify every electron in our atoms, while stuff-electrons have no individual “identity” to speak of.

A stuffium universe would be drastically different to ours; there is no energetic barrier to the formation of heavier elements such as iron (ahem, stuffium-26), and most of these elements would exist in even denser polyatomic molecular forms. The abundant presence of these heavier elements and molecules leads gravity to form galaxies much quicker than they began to form in our universe, and most nebulae would rapidly collapse into massive, dense planets. Black holes would be a common sight, and with chemistry changing completely, it’s unclear if stars could even exist. Cool beans!

Light & Gravity (or Stuff and Some Other Stuff)

Now there’s not a lot of different kinds of stuff in the universe, but here’s a big one: Light is stuff! This is actually pretty intuitive, as I’m sure you’ve noticed that light doesn’t really behave like most things (pardon the pun) you’ve seen before. For one, clearly unlike things, you can essentially pile up “identical” light indefinitely just like the stuffium electrons above*. In fact, piling up identical light and then emitting it is precisely the definition of a laser.

*Eventually, piling up extremely large amounts of light creates things out of stuff, but that’s way out of our league here.

Gravity, or more accurately what causes it, is also stuff. This is actually a bit of a mind-boggler, since we haven’t really discovered the stuff that causes gravity; but we know for sure that it has to be stuff because gravity just wouldn’t be gravity if it wasn’t. Sadly there’s not much more to say about gravitational stuff at the moment, but we’re working on it.

At the risk of complicating things even more, scientists have actually discovered ways to make things behave like stuff! For example, in certain materials, you can actually trick every available electron (all ~10^23 of them) into piling up into the same material-wide shape, leading to some extremely strange phenomena.

Anyways, before I finish off this post, I should probably reveal the scientific names for things and stuff; now you can brag that you know what the second part of that whole “Higgs boson” hullabaloo means! (Admittedly, Higgs stuff doesn’t sound as interesting).