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Cosmic Soup

I once heard someone (I think it was Neil deGrasse Tyson, but I might be wrong) describe the universe with a really cool analogy: it’s just like soup. You take onions and carrots and celery and mushrooms and rice and stick them in some water. Starting out, it’s not a soup. It’s a disgusting bunch of vegetables floating in some nasty cold water. But as it cooks, all the ingredients leach good stuff into the water and flavor each other, and eventually, you’ve got soup.

Which is a surprisingly good analogy for how our universe formed (at least, according to the best cosmological models we have as of January 2015 (I hate having to add that every time, but it’s true)). First, there was the big bang, which we know little about. The big bang cooled down and gave us a bunch of hydrogen, a little helium, and a tiny trace of lithium. Then it got too cold to make heavier atoms. Luckily, gravity kicked in. The hydrogen and helium (with some help from whatever the hell dark matter actually is) clumped together to form gas clouds. Those gas clouds collapsed to form stars. Those first stars were huge and bright and hot and died young. They died in massive supernovae, releasing heavy elements from their cores and creating new heavy elements on the spot from their high-energy radiation. Slowly, these heavier elements accumulated in the interstellar medium. Eventually, they started getting incorporated into the molecular clouds that went into forming new molecular clouds (I’m getting a horrible unwholesome image of a room full of people breathing each other’s flatulence; that’s why Neil deGrasse Tyson is on TV and I’m sitting here in my corner). These new molecular clouds could collapse to form not only stars, but also things like planets. And this went on and on until we reached today, which is (we think) about 14 billion years later. We’ve got chemistry all over the damn place. There’s chemistry in the sky and chemistry in the oceans and chemistry up to the tops of the highest mountains. My brain is full of chemistry (and from the sound of that sentence, my chemistry’s a little off again tonight…)

But what if it had happened differently? I mean, I’m pretty pleased with how our cosmic soup turned out (seeing as it allowed me to exist and all, which was nice of it), but you’ve got to admit that hydrogen, helium, and a tiny bit of lithium is pretty bland. It’s like that watery potato soup they give orphans in Christmas movies. Sure, it’ll keep you alive, but it’s not all that interesting. So what would happen if we started out with some different ingredients? What would we end up with then?

Let’s find out!

The Gumbo Universe: This universe starts out with a little of everything. Like I said, our universe started out with hydrogen, helium, lithium, and almost nothing else. And there’s a good physical reason for that: it cooled off so fast that there wasn’t time for anything more complicated than helium and lithium to form. It’s like flash-freezing: you don’t get any interesting crystals if you cool your water down too fast.

But in the Gumbo Universe, there are no such limitations. The universe starts out with all of the stable elements. The abundance of a given element is determined by its atomic number. Helium is ten times rarer than hydrogen. Lithium is ten times rarer than helium. And so on. The Gumbo Universe is 90% hydrogen, 9% helium, 0.9% lithium, 0.09% beryllium, 0.009% boron, 900 parts per million carbon, 90 parts per million nitrogen, 9 parts per million oxygen, 900 parts per billion fluorine, 90 parts per billion neon, and so on until uranium, element 92, which would make up only 90 atoms out of every 1, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000.

To my surprise, the Gumbo Universe’s hydrogen-to-helium ratio is pretty close to ours. But this universe has a massive overabundance of lithium, beryllium, and boron. These elements aren’t heavy by human standards (lithium floats in water, although not for very long, since it tends to catch fire and explode), but they might as well be lead boots as far as the cosmos is concerned. All these surplus heavy elements mean stars are going to form sooner, be denser, and probably start fusion sooner. Collisions with high-speed protons (i.e., the hot hydrogen atoms surrounding the metal-rich cores of these weird stars) will rapidly convert most of the lithium to helium (which also happens in our universe). The same thing will happen to the boron (interestingly, proton-boron fusion is being studied in our universe, since it doesn’t produce neutron radiation, which (because it’s evil) damages DNA and turns innocent substances radioactive). And when those beryllium atoms get hit by alpha particles (which are the same thing as hot helium nuclei, which, again, we’re going to have plenty of), they’ll turn into carbon and neutrons. The same thing happened in our universe, which is why, in element abundance graphs like the one in this paper, there’s a massive dip in abundance from lithium to beryllium to boron. Actually, physics ensures that, since the element composition of the Gumbo Universe starts out pretty similar to that of our universe, its ultimate composition is probably going to be similar, too.

Its structure, on the other hand, won’t be. At my estimate, I’d need at least four separate PhD’s and a supercomputer (which still I don’t have. Stupid thrift stores. Never have anything good.) to provide even a good guess what state the stuff in the Gumbo Universe would be like. I suspect the stars would be smaller, since their heavy-element cores would let them ignite fusion earlier, and their light would blow away what remained of their molecular clouds. These stars would probably be red dwarfs (or their exotic cousins), but probably wouldn’t be as long-lived as red dwarfs in our universe. As for galaxies, they’d probably still form (galaxy formation is driven mainly by the gravitation of matter and dark matter (whatever the hell it is)). As for whether they’d be larger or smaller than the galaxies in our universe, I can think up good arguments for both. I can see them being smaller because so many stars would form so quickly, which would blow away a lot of gas and slow star-formation rates, meaning lots of little galaxies a lot closer together. But then again, if the stars in the Gumbo Universe are red-dwarf-like, then their radiation pressure will be pretty weak, which might actually let galaxies grow larger than they do in our universe. I leave that as an exercise to the reader (which is the smart-ass way of saying “I can’t be bothered.”)

But what about the question that has plagued us (probably) since the dawn of thought: Could there be life forms in the Gumbo Universe? (Okay, I’m guessing Galileo didn’t ask himself that exact question, but you know what I mean. Although for some reason, I’m thinking Galileo would have really liked gumbo.) That’s really hard to answer. We know there’s life in our universe, but we don’t know how hard it is for life to form, how long it lasts once it forms, and whether it tends toward simplicity or complexity. But my guess is that the Gumbo Universe would be even more fertile than our own. It would have the elements needed to make life (hydrogen, carbon, oxygen, nitrogen, phosphorus, sulfur, et cetera) right from the start. And to boot, with its smaller stars, it would (probably) have fewer supernovae, which means larger portions of the galaxies would be habitable, since supernovae are probably very unhealthy for life as we know it.

The Julia Child Universe: Julia Child was famous for a lot of things. She was famous for her PBS cooking shows, for her attention-getting voice, for her love of cooking, and for being shockingly tall (6’2″ (188 cm), if IMDB is to be believed). I grew up watching her, but she was cooking on TV when my parents were children. She was famous for her show The French Chef, and one of her most famous recipes (and also the last meal she ate before she died, if Wikipedia is right) was her french onion soup. French onion soup is pretty much just finely-chopped onions simmered in beef stock.

And why on Earth, you may be asking, am I talking about TV chefs and onion soup? Because the French Onion Soup universe, like french onion soup itself, has very few ingredients. The French Onion Soup universe is made entirely of Uranium-238. You might be saying “That’s absolutely ridiculous.” And you’d be right. But I’ve never let that stop me before.

Well, to nobody’s surprise, the Julia Child Universe would be weird. We’d start out with a bunch of gaseous uranium plasma which would gradually cool and coalesce into little dust grains. Those dust grains would collapse. Since fusing two uranium nuclei requires an external energy input, there wouldn’t be any ordinary stars to begin with. There would, however, probably be medium-temperature white dwarfs and neutron stars, which would form straight from the interstellar medium, shortcutting all that hydrogen-burning nonsense stars in our universe have to go through. And, for the same reason all the planets in our solar system don’t get sucked into the sun and all the stars in our galaxy didn’t get sucked into the supermassive black hole at the center (the reason mostly being angular momentum), there would probably also be uranium planets.

Uranium-238 is pretty stable. It’s stable enough that, if you swallow it, your biggest problem isn’t that you just swallowed something radioactive; your biggest problem is that uranium is a toxic heavy metal. But it is radioactive, and when you’ve got enough of it in one place, that radioactivity adds up. U-238 is, for instance, one of the reasons Earth’s interior stays hot enough to be fluid.

But now we’re talking about planet-sized masses of U-238. If Earth were made entirely of uranium, it would have a radius of something like 4,000 kilometers, 60% of its actual radius. It would also produce 5e18 watts of heat from alpha decay (at least at the start of its life), which would be enough to make it glow cherry-red and probably melt.

Sadly, no planet is immortal, even when it’s made of solid uranium. U-238 decays (with a half life of 4.468 billion years) into Thorium-234, releasing an alpha particle (helium nucleus). Over time, the alpha particles will steal electrons from the uranium and thorium atoms, and all those uranium planets will develop helium atmospheres. But it doesn’t end there: Thorium-234 decays (by emitting an electron) with a half-life of 24 days into metastable Protactinium-234 (metastable meaning the nucleus is excited, and will therefore probably release a gamma ray). Regular Protactinium-234 decays by electron emission to Uranium-234, with a half life of 1.17 minutes. Uranium-234 is also an alpha emitter, meaning it decays into Thorium-230 and helium. Thorium-230 decays into helium and Radon-226, which has a half life of around one and a half thousand years. (And for those who are picky and obsessive like me, yes, there would be small quantities of other elements produced by things like spontaneous fission and cluster decay, but I’m keeping things simple.)

This is one weird planet we’ve got. By the time enough of it has decayed to give it an atmosphere as substantial as Earth’s, it’s still probably hot enough to glow. And that atmosphere is just about as toxic as you can imagine: it’s composed primarily of helium, so your voice would be all funny. The helium would also be scorching-hot, so your voice would get really funny. And it would be extremely dense and seriously radioactive, making it even worse than Venus’s atmosphere (which is the closest thing I can imagine to actual Hell).

But the decays would go on. Radon-226 is a noble gas. It decays into Radon-222 (again, by alpha decay), and then into Polonium-118 (not the kind of Polonium people use to poison Russian guys). As it decayed, there would be a fine snow of extremely radioactive isotopes, which would probably give the air an extremely faint blue glow. Most of those isotopes have half-lives measured in minutes or seconds (or microseconds), but you’d most likely end up with measurable quantities of Polonium-210 (that’s the kind you use to very suspiciously murder Russian guys), Lead-210, and Bismuth-210. But all roads that start at Uranium-238 eventually reach Lead-206 (sounds like a really terrible Johnny Cash parody). Lead-206 is stable, and makes up about a quarter of the lead atoms we find here on Earth (there are other stable isotopes). So, after around 4.4 trillion years, there would be less than one one thousandth of the original U-238 left. Pretty much everything else would be either lead or helium.

But that’s not the end. During its transformation to Lead-206, Uranium-238 has given birth to no less than 8 alpha particles, which will ultimately become helium atoms, So, after a long time, the mass of the Julia Child Universe would consist of 84.5% Lead-206 (by mass) and 15.5% Helium-4. 15.5% of one solar mass (in our universe, and when it’s made out of hydrogen) is enough stuff to make a proper star (albeit a small one). It’s harder to make a star out of helium, though, since helium atoms take more energy to fuse together. Stars weighing 15.5% of a solar mass generally can’t burn helium. That is, unless they have enormously dense, hot cores with crushing gravity. Which would most certainly be the case of some of our uranium white dwarfs and our neutron stars. So, for a brief while, stars would burn in our weird-ass sky. I say “a brief while” because, when you compress it to such high pressures and densities, helium tends to detonate more than burn. Our stars would last a few hours or a few days, burning purplish-white with fusion energy.

Helium fusion is a little complicated, which is why it takes stellar pressures to get it going. First, two helium nuclei fuse to form Beryllium-8. Then, another helium nucleus fuses with Beryllium-8 to form Carbon-12, which is the carbon on which our chemistry is based. But it gets better: it turns out that you can keep adding helium nuclei until you get all the way up to Iron-56 and Nickel-56, after which the fusion no longer releases energy. You’d end up with most of the ingredients for life as we know it, although they’d all be stuck on the surface of white dwarfs and neutron stars. Still, Frank Drake and Robert L. Forward made a passable case for life on a neutron star in Dragon’s Egg, so who knows? And white dwarfs tend to hold their heat for billions of years, so you might see very flat critters crawling around on miniature lead stars.

Surprisingly, even this weird universe would ultimately produce planets made of more familiar stuff. It turns out that collisions between neutron stars can produce elements like thorium and gold, and other elements which could fission into lighter elements. Neutron star collisions are pretty violent things, so some of this stuff would get flung out into space. Neutron stars have a death-grip on their matter, so I imagine it wouldn’t be nearly enough to form an actual proper hydrogen star, but it would probably be enough to form a planet.

Imagine it: a planet made of gold, iron, carbon, and uranium, with an atmosphere of helium and carbon dioxide, inhabited by radiation-hardened snails with lead shells. Sound implausible? How could it possibly be more implausible than the star-nosed mole?

The “Blinded by the Light” Universe: Can you tell my mom made me listen to too much classic rock when she was driving me to school? Until now, all our hypothetical universes have been made of matter: protons, neutrons, and electrons. But what if the mass of the universe was composed entirely of photons? That is, particles of light.

This one’s a lot trickier. In order for anything really interesting to happen, the universe has to expand in just the right way, and there has to be just the right number of photons. If the universe expands too fast (which can happen when there are too few photons) or too slow (if there are too many photons), it’ll end up as a diluted infrared soup (the former case) or a singularity (the latter). But if everything goes just right, and the universe expands and then comes to a halt while at least some of the photons have energies above 1022 kiloelectronvolts (meaning wavelengths shorter than 0.0012 nanometers), then interesting stuff can happen.

The universe is really weird. A gamma ray with an energy of 1022 kiloelectronvolts effectively has twice the mass of an electron. Thanks to quantum mechanics (the giver of headaches, by royal appointment), a gamma ray with an energy equal to or greater than 1022 keV can suddenly turn into an electron and a positron (its antiparticle). Normally, photons can’t interact with each other, since they have no charge. But if one photon should collide with another photon that’s momentarily popped apart into two charged particles, then they can interact. Sometimes, they can even bounce off of each other (see this Wikipedia article for a brief introduction).

But what exactly does that mean? Well, to be honest, I’m not sure. Photons are complicated. They have energy and angular momentum and all sorts of other stuff they didn’t teach in the English department. I don’t know whether life or intelligence of any kind could exist in this universe. But I imagine interesting structures could emerge, as long as there were enough high-energy gamma rays left over. I’m imagining a Feynman diagram big enough to wallpaper an airplane hangar, covered in a terrifying spiderweb of lines, photons bouncing off photons and transferring angular momentum back and forth. Let’s face it, that wouldn’t be any wilder than the universe we have: a soup of photons bouncing off of electrons, and electrons shuffling between atoms made of protons and neutrons.

The Universe is Made of Spiders: The Spider Universe has no explanation. It consists entirely of spiders which weave airtight tubular webs containing long-lived radio-isotopes. Plaques of mold feed on these isotopes. Fruit flies feed on the mold. Spiders feed on the fruit flies, and endlessly weave. Their air-filled tunnels are no thicker than your finger, and spread so thinly that each is separated from its nearest neighbor by the diameter of a star. But they’re all connected. Even though no single spider will ever travel from one node to the next in its lifetime, there is a steady traffic of genes to and fro. An endless parade of spiders, back and forth, back and forth in a network far more fragile and gossamer than the thinnest gold leaf.

In case you’re worried I just had a seizure there, I didn’t. I think. You see, according to recent physics, the universe as it exists today will collapse if its density is greater than one hydrogen atom per cubic centimeter. Locally, the density can be much higher (like, for example, on Earth). The same applies to mysterious networks of radioactive spiderwebs that appeared from nowhere at the beginning of time with no explanation. And when you consider that our current cosmological models pretty much all say “First there was the Big Bang, which for some reason created a bunch of energy and matter (but more matter than antimatter, for some reason). We don’t know why, but then everything else happened”, the spider thing doesn’t seem so far-fetched. Okay, maybe a little far-fetched, but isn’t it cool that we still have stuff to learn about the start of the universe?

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Imagining is fun. Dimethylmercury sucks.

Among the many silly things with which I like to amuse myself, Wolfram Alpha is probably in the top five. It makes ridiculous hypothetical questions (which are probably my favorite thing of all) much easier to answer. For instance:

What if I had a cubic meter of depleted uranium sitting in my yard? Well, for starters, it would weigh 19,050 kilograms, which is the mass of 12.09 Lamborghini Diablos. (I’m actually not sure which would be cooler. Probably the Lamborghinis, unless you’re the unlucky bastard who gets the 0.09.) If you divide the weight (gravity times mass) of the cube by the area of its footprint (one square meter, because I demand perfect symmetry in my uranium cubes), you get a number called “ground pressure.” When it comes to things like bicycles, cars, cranes, and horrifying mechanical spider-demons like the Bagger 288 excavator, ground pressure tells you whether the vehicle’s weight is spread over a large area or concentrated into a small area and therefore likely to fuck up somebody’s lawn. My cube’s ground pressure comes out to 187 kilopascals (27 psi), which is about the same as that of a passenger car, which means the cube’s gonna be no good for the grass.

You know what else is gonna be no good for the grass? The radiation. Oh yes, there will be radiation. I specified depleted uranium, which isn’t as nasty as the U-235 they make bombs and reactors from (well, reactor fuel; I don’t think the build the actual reactors out of uranium. That would be silly), but it’s still radioactive. It gives off alpha particles. My whole cube would emit about as much radiation as 74 grams of Cesium-137. Basically, I’m going to have another big dead spot in the lawn.

On the other hand, all that radiation releases thermal energy, energy I can use to…well…power a single LED. U-238 isn’t that radioactive, so the whole cube would only release about 0.1 Watts as alpha particles. So it’s not technically useful. And it’s actually technically an enormous quantity of a toxic heavy metal which is technically close enough to nuclear fuel that I’ll probably be getting a visit from some men with sunglasses and creepy Agent Smith earpieces. Wait, why did I want a cubic meter of depleted uranium again?

Okay. Let’s not do that. What if, instead, I had 1 trillion grains of salt? You know, there are certain foods which are common enough and uniform enough that we can use them as really weird measuring-sticks. For instance: when I think of 1 millimeter, I think of a peppercorn. When I think of 1 centimeter, I think of a blueberry. And when I think of sand-sized things, I think of grains of table salt, which in their homogenized commercial form are about 300 microns on an edge. That’s good news for us: it means I can tell you just how a big a pile my 1 trillion grains of salt will make. 
Pretty big, as it turns out. The pile will be almost 3 meters (over 9 feet) high and twice as wide. I think I’m starting to realize where all these dead spots in the lawn are coming from. I’m also starting to realize that 1 trillion is a really big number. 1 trillion grains of salt would fill a standard 40-foot shipping container almost halfway. All we need now is several swimming pools to put it in, and we can have pickles forever.
What if it rained mercury instead of water? Yes, I am aware that I’m kind of copying Randall Munroe of xkcd fame here. No, I am not ashamed to admit it. xkcd is awesome.
Based on YouTube videos like this one, and the fact that mercury has a surface tension about 5 times higher than water’s, we can assume that our mercury rain (Which will not inspire as many popular songs as chocolate rain, I’m sure. Partly because we’ll all be dead.) will fall in much smaller drops than ordinary rain. We also know this because mercury is so much denser than water (it’s so dense almost every other substance floats on it, including lead, granite, and iron). This density means that the mercury raindrops would be heavy enough to fall from their clouds at a smaller size than water raindrops.
The average water raindrop has a radius of about 1 mm, and therefore weighs about 4.2 grams. A 4.2-gram mercury drop has a radius of 420 microns, so it’s about the size of a poppy seed (See? Useful! Why don’t we measure everything in food units?). The terminal velocity of a water droplet with a radius of 1 millimeter is about 6.6 meters per second or 15 miles per hour. The terminal velocity of our mercury drop is 15.7 meters per second or 35 miles per hour. The impact of each mercury drop would be like being hit by a bug while riding a motorcycle at moderate speeds, which would be annoying, but probably not painful.
“But Hobo,” I hear you ask, “isn’t mercury deadly poison?” Well, yes. But elemental mercury, the kind that forms pretty shiny droplets, is one of the less poisonous forms. I’m not saying it’s good to have around: it gives off vapor which, when breathed, can poison you, make you go insane, and inspire an Alice in Wonderland character. But as long as it’s on the outside of your body, mercury isn’t instantly lethal. Just take a few showers after the mercury rain and you’ll be okay.
If you get elemental mercury inside you, however, you’re in big trouble, as in the tragic case of a woman who injected liquid mercury directly into her arm in 1967, in what I can’t help but think must have been a suicide attempt. A few days after the injection, they X-rayed her lungs and saw droplets of mercury in the blood vessels. She developed a fever of 107 Fahrenheit (41.8 Celsius) and died 31 days after the injection.
But unless you’re breathing or swallowing or otherwise consuming it, it’s not metallic mercury you should be worried about. It’s organic mercury–mercury that’s joined up with carbon atoms. Infamously, methyl-mercury (which consists of a carbon atom stuck to a mercury atom, paired with a negative ion like chloride) tends to accumulate in the most delicious kinds of fish (like tuna), which is a real shame. 
But methyl-mercury is nothing. Methyl-mercury may lead to brain damage and environmental pollution, and that’s tragic, but for sheer shock value, nothing surpasses dimethylmercury. In a famous (and again, really sad) case in 1997 (which is just as scary in this emotionally-neutral medical report as it was in the news), an experienced chemist was transferring dimethylmercury from a vial into a test tube. Her area of expertise was the chemistry of heavy metals, so she had a reason to be messing with this stuff, and she knew what she was doing. But she accidentally spilled a few drops of the stuff on her hand. Being safety-conscious, she removed her latex glove and presumably washed her hands and went back to work. 
For five months, it seemed there was nothing wrong. Then, suddenly, she started losing her balance and slurring her words. She went to the hospital. Over the course of a month, in spite of really, really aggressive treatment, she lost feeling in her feet and hands, lost her hearing and vision, and fell into a vegetative state, and was eventually taken off life support, per her wishes. On autopsy, her brain’s entire cortex was atrophied and scarred. Her cerebellum, which controls balance and coordination and other functions, was almost completely destroyed.
I would like to remind you that all this happened because she spilled two or three fucking drops of dimethylmercury on her hand which was protected by a latex glove. Didn’t matter. Dimethylmercury is just that nasty. 
Luckily, the scientific community has said what we all want to say right about now, which is “Go fuck yourself, dimethylmercury.” There was a time when people used it to calibrate nuclear magnetic resonance machines, but even the NMR people, who spend their days dealing with magnetic fields that can turn paperclips into deadly missiles, have given dimethylmercury a big middle finger. And good for them. That’s some nasty shit.
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