Let’s boldly assume that the multiverse hypothesis is true, and a set of universes exists outside of our own.

“We wouldn’t actually be able to check if there are aliens in alternate universes, because there’s no way to get to those universes if they do, in fact, exist,” says LSA senior Kate Coppess. Instead, she set out to calculate the probability of extraterrestrial life populating one of these hypothetical alternate cosmos.

Spoiler alert: Yes, life is possible in other galaxies far, far away.

“All of the physical laws in our universe are governed by around six fundamental constants, like the strength of gravity, the strength of electromagnetic forces, and the masses of particles,” she says. “What a lot of scientists are wondering is why those constants take on the values that they do and whether the fundamental physical properties in our universe are unique in the potential to develop life.”

Coppess spent last summer thinking about these questions as an Honors Summer Research Fellow. The interdisciplinary LSA fellowship supports student researchers like her, along with other students who are interested in a range of topics, such as the psychology of eating disorders and witches in ancient Roman literature. “The fellowship provided a community over the summer,” says Coppess. “Everybody really cared about what they were doing, and that was infectious. I felt like I learned a lot from everybody else.”

Coppess turned her summer research into an honors thesis—calling it “Habitability in Alternate Universes”—with guidance from her advisors, Physics Professor Fred Adams and Math Professor Anthony Bloch.

 

Illustrations by Erin Nelson

 

To begin, Coppess plunked down in front of her computer and wrote about 200 lines of code that modeled a universe defined mainly by our universe’s physical constants, but she specified two things: Life requires liquid water, and life can arise only if a planet doesn’t collide too often with other large objects. “If we were being bumped into every couple million years,” she says, “life wouldn’t be able to evolve because of those big disruptions.”

Then she ran her simulations, manipulating a single characteristic in her synthetic alternate universe: the density of a galaxy’s planets and stars. Coppess marked as habitable those areas of her simulated galaxies that satisfied the two specifications in her model.

Her conclusion? “The potential for habitability in a universe is not unique to our own. We found that it’s possible for there to be more habitable planets in those alternate galaxies than in our own galaxy,” Coppess says. “The conditions in our universe may not actually be ‘the best.’”

The results raise a surprising paradox. If the conditions of our universe actually are notideal for facilitating life, then why does Earth seem to be the only planet around that actually contains creatures? “It’s kind of amazing that we’re here,” says Coppess.

What she’s found has relevance in physics, of course, but also carries philosophical significance. Coppess says that her research not only provides perspective on how ‘ideal’ the conditions of our universe are, but also brings us closer to answering the question of our uniqueness.

“It’s interesting that our universe isn’t unique with respect to having the potential for life,” she says. “I guess we’re lucky that we were able to evolve to this level, in a universe that’s not ideal for developing life.”