# Science and the vampire/zombie apocalypse

It seems like every time I turn on the TV, which only occurs when I’m in the exercise room, there is a show that involves either zombies or vampires. From my small sampling, it seems that the more recent incarnations try to invoke scientific explanations for these conditions that involve a viral or parasitic etiology. Popular entertainment reflects societal anxieties; disease and pandemics is to the twenty first century what nuclear war was to the late twentieth. Unfortunately, the addition of science to the zombie or vampire mythology makes for a much less compelling story.

A necessary requirement of good fiction is that it be self-consistent. The rules that govern the world the characters inhabit need to apply uniformly. Bram Stoker’s Dracula was a great story because there were simple rules that governed vampires – they die from exposure to sunlight, stakes to the heart, and silver bullets. They are repelled by garlic and Christian symbols. Most importantly, their thirst for blood was a lifestyle choice, like consuming fine wine, rather than a nutritional requirement. Vampires lived in a world of magic and so their world did not need to obey the laws of physics.

Once you try to make vampirism or zombism a disease and scientifically plausible in our world, you run into a host of troubles. Vampires and zombies need to obey the laws of thermodynamics, which means they need energy to function. This implies that the easiest way to kill one of these creatures is to starve them to death. Given how energetically active vampires are and how little caloric content blood has by volume, since it is mostly water, vampires would need to drink a lot of blood to sustain themselves. All you need to do is to quarantine all humans into secure locations for a few days and all vampires should either starve to death or fall into a dormant state. Vampirism is self-limiting because there would not be enough human hosts to sustain a large population. This is why only small animals can subsist entirely on blood (e.g. vampire bats weight about 40 grams and can drink half their weight in blood). Once, you make vampires biological, it makes no sense why they can only drink blood. What exactly is in blood that they can’t get from eating flesh? Even if they don’t have a digestive system that can handle solid food, they could always put meat into a Vitamix and make a smoothie. Zombies eat all parts of humans so they would need to feed less often than vampires and thus be harder to starve. However, zombies are usually non-intelligent and thus easier to avoid and sequester. It seems like any zombie epidemic could be controlled at very early stages. Additionally, why is it that zombies don’t eat each other? Why do they only like to eat humans?  Why aren’t they hanging around farms and eating livestock and poultry?

Vampires and sometimes zombies also have super-strength without having to bulk up. This means that their muscles are much more efficient. How is this possible? Muscles are pretty similar at the cellular level. Chimpanzees are stronger than humans by weight because they have more fast twitch than slow twitch muscles. There is thus always a trade-off between strength and endurance. In a physically plausible world, humans should always find an edge in combating zombies or vampires. The only way to make a vampire or zombie story viable is to endow them with nonphysical properties. My guess is that we have hit peak vampire/zombie; the next wave of horror shows will feature a more plausible threat – evil AI.

# Technology and inference

In my previous post, I gave an example of how fake news could lead to a scenario of no update of posterior probabilities. However, this situation could occur just from the knowledge of technology. When I was a child, fantasy and science fiction movies always had a campy feel because the special effects were unrealistic looking. When Godzilla came out of Tokyo Harbour it looked like little models in a bathtub. The Creature from the Black Lagoon looked like a man in a rubber suit. I think the first science fiction movie that looked astonishing real was Stanley Kubrick’s 1968 masterpiece 2001: A Space Odyssey, which adhered to physics like no others before and only a handful since. The simulation of weightlessness in space was marvelous and to me the ultimate attention to detail was the scene in the rotating space station where a mild curvature in the floor could be perceived. The next groundbreaking moment was the 1993 film Jurassic Park, which truly brought dinosaurs to life. The first scene of a giant sauropod eating from a tree top was astonishing. The distinction between fantasy and reality was forever gone.

The effect of this essentially perfect rendering of anything into a realistic image is that we now have a plausible reason to reject any evidence. Photographic evidence can be completely discounted because the technology exists to create completely fabricated versions. This is equally true of audio tapes and anything your read on the Internet. In Bayesian terms, we now have an internal model or likelihood function that any data could be false. The more cynical you are the closer this constant is to one. Once the likelihood becomes insensitive to data then we are in the same situation as before. Technology alone, in the absence of fake news, could lead to a world where no one ever changes their mind. The irony could be that this will force people to evaluate truth the way they did before such technology existed, which is that you believe people (or machines) that you trust through building relationships over long periods of time.

# Selection of the week

Let’s stay with some more movie music.  Here is John Williams conducting his theme to Jurassic Park with the Boston Pops.

# The problem with sci fi movies

I, like many people, enjoy science fiction films. The biggest problem I find in these fictional universes is not that sounds can propagate through space, people can travel at the speed of light with no relativistic effects then decelerate to a stop in a few seconds and not even be knocked to the floor, be able to generate artificial gravity everywhere, have power sources that rarely need refueling, and so forth. I accept that these are convenient plot devices that keep the story moving forward. Although I do have to say that successful films like 2001: A Space Odyssey and more recently Interstellar and The Martian show that trying to be faithful to science can often provide an even better plot device. I am still impressed by the special effects in 2001 and the amazing attention to detail of director Stanley Kubrick, e.g. near the beginning of the movie when they are on the rotating space station you can see the subtle curvature of the floor inside the rim. I hope the success of these movies lead to more realistic science fiction and even realistic action movies where the violence is realistically portrayed – people can’t be hit by a brick and then get up.

No, the thing that most irks me about science fiction movies is that the film makers either refuse or are too lazy to make their universes self-consistent. This list is in no particular order and is by no means exhaustive.

1. Why do storm troopers in Star Wars movies wear plastic suits if they don’t protect them from anything?
2. In an age with extremely powerful computers and communication devices, why should various control systems only be accessed at specific locations in a building or space craft. Do you really need to go to the engine room to fix the engine? Haven’t they progressed beyond a WWII aircraft carrier?
3. Why are weapons in the future so bad? Why do people ever miss? There is self-aiming, self-guided bullet technology now and in a future universe with flying cars no one has thought of making this? This also goes for space crafts still engaging in dog fights like the Battle of Britain in 1940.
4. In the Avenger movies, Iron Man Tony Stark invents a fusion reactor that can fit in his chest and power a flying suit for at least the duration of the movie without ever refueling. Shouldn’t this have transformed the world? This could solve global warming if not end global poverty. Even if he is not making the invention public shouldn’t the rest of the world be working on this?
5. In the Hunger Games series they have technology to make mutant animals and plants so why is there hunger? They have a ban on GMO’s for food? Why do they still need coal mining or at least need people to do it?
6. My very first blog post was about the thermodynamic impossibility of the premise of the Matrix movies. Stupid premises seem to be a major problem with the Warchowski sibbling’s films that I have seen. They have this pretense for being intellectual and try to infuse their films with a social consciousness but unfortunately fail. The theme in both the Matrix and the more recent film Jupiter Ascending (JA) is that there is an evil future society that treats humans as commodities – as energy in the Matrix and as a source for an immortal elixir in JA. That could be fine if in JA there was something mystical about humans that could not be reproduced elsewhere but what the Warchowskis do instead is try to infuse some science in it so it is not magic. There is a proto-human race that caused the dinosaurs on earth to go extinct so that humans could arise and then waited 65 million years before they could harvest them for the elixir. That was the easiest way to create a farm for humans? A second premise is that the heroine of the movie is an exact genetic replica of a former Queen who owns earth and who bequeathed her wealth to anyone who is a genetic replica. Again, the Warchowskis forgot to do their math. The probability of an exact genetic replica coming from chance, which is what they insisted on, would be at most 1 in $2^{10,000,000}$ (if differences are only biallelic common variants), which is unimaginably small. The proto-humans are also billions of years old but have not evolved in any way over that time even though squirrel-like creatures turned into humans in 65 million years on earth.
7. Even in the movie Interstellar, there is a future race of humans that have the technology to tame a black hole and send messages to the past but they can’t send back instructions for making crops that will grow on earth?

I appreciate that some of these movies are not about science or the future but remakes of old western, adventure, or war movies. However, some are really trying to portray a possible future. If that is the case then some amount of self-consistency is necessary to make the story compelling. One very possible future that I don’t see being explored in popular movies is that unlike dystopian futures where there is a return to feudalism and people are exploited by evil overlords or capitalists, a real problem we may face is that people will become obsolete. People should make movies about what a world where machines can replace almost everything people do would look like. In fact a better premise for the Matrix is that we chose to live in a big simulacrum and a subset of us rebelled. Now that would be an interesting movie.