How it works
Alemi and coauthors modeled out the population centers of the country and then assumed certain possible interactions, with an element of randomness. A zombie might bite and infect a human or the person might escape or kill the creature. And of course, the undead shamble onward.
Also, in reality, an outbreak probably wouldn't start all over the country, and there are some variables. The undead might be more or less aggressive or more or less mobile.
So the research team built an interactive model that allows you to simulate an outbreak, picking a starting point, a zombie-bite to zombie-kill ratio, and whether the zombies are fast or slow.
As you can see in the GIF below, a fast-zombie outbreak in New York City would be devastating within 24 hours.
Not looking good. More complex variables would be interesting, though.
"Given the time, we could attempt to add more complicated social dynamics to the simulation, such as allowing people to make a run for it, include plane flights, or have an awareness of the zombie outbreak, etc.," Alemi said in the press release.
While zombie scenarios might seem like something a bit silly for researchers to spend time on, public health researchers tend to like these sorts of scenarios since they help educate people on how diseases spread. The CDC even maintains a "Zombie Preparedness" page.
Physicists seemed to want to be prepared. The talk was reportedly standing-room only.
This story was originally published in 2015.
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