Kill the sun! How wild thought experiments drive scientific discovery

Listen, I don’t actually want to kill the sun – I just want to know. how. However, when I told my colleague, new scientist When I told them I was recruiting scientists to do this, I got puzzled looks. I write about space every day, and I find it endlessly fascinating. I have an affinity for the mysteries of the universe, so why would I want to ruin any part of it, let alone kill our beloved and essential star?

Despite their confusion, my colleagues coddled me and my partner in ruin, American editor Chelsea White. We started reaching out to free-thinking astrophysicists and planetary scientists and asked them to join our podcast, Dead Planets Society. With them, we began to tinker with the universe – at least in our minds – not only to kill the sun, but to imagine a gravitational wave apocalypse, to slice the moon in half, to cube the Earth. I imagined what it would look like if I carved it.

As we thought of questions to ask our guests (all of whom are university professors and proper scientists), we looked up trivia about gravity and planetary science, learned about escape velocity and Roche… I realized that I was calculating my limits. Podcasting was just a fantasy, a fun game, but it started to feel a little like science. We have found that seemingly absurd thought experiments have always been central to the scientific method.

Philosophers say science began with thought experiments, not with demonstration experiments conducted on benches or telescopes. H. Peter Steves At DePaul University. Galileo Galilei, one of the founders of modern scientific method in the 16th century, is remembered for dropping a feather and a hammer from the Leaning Tower of Pisa. The story goes that by demonstrating that objects fall at the same speed, Galileo overturned his 2,000-year-old ideas about how gravity works. “[It] “It’s about as fanciful as Newton getting hit in the head with an apple,” Steves says. “But there is evidence that he engaged in a thought experiment to prove how wrong Aristotle’s concept of gravity was.”

Over the course of history, we have become much better at conducting practical experiments, but thought experiments are still important. For example, Albert Einstein is famous for his struggle with gravity, which completely changed our view of the universe and conjured up absurd scenarios in our heads. One evening, while riding a streetcar, he imagined what the world would look like if he were traveling at the speed of light. This was the seed that grew into his special theory of relativity in 1905, after years of frustration trying to explain the behavior of light. “When you imagine things on such a grand scale,” says the philosopher, “the familiar things become expressed in a different way.” Guy Kahane at Oxford University.

This is true even today. Indulging in thought experiments is common among theorists trying to understand black holes and what these extreme objects reveal about the nature of reality. For example, a black hole’s strong gravity means that scientific instruments cannot be placed right next to or inside a black hole to send data back. So theorists spend a lot of time thinking about and calculating what would happen to an observer in any of these positions, and they come up with all kinds of surprising insights about concepts like time and causation. be connected. “When you think in this playful way, you start to see things that you wouldn’t otherwise see,” Kahane says.

The first episode of Season 2 of Dead Planets Society runs its own black hole thought experiment. Black holes are often thought of as giant cavities that swallow everything that approaches them. Black holes are the ultimate destroyers. So what can we learn by trying to destroy it? To look for a black hole’s weak point, we can either use a spaceship with infinite speed to escape from the black hole with some of the black hole’s mass, or use an unrealistically strong magnet to I considered tearing the hole apart. Although we can’t actually build these cosmic tools, imagining them has reshaped the way we think about black holes.

In the process of recording the episode, this made us think about black holes in a new way. Using quantum mechanics, they can be described as incredibly massive objects that happen to have escape velocities faster than the speed of light. Or, according to general relativity, they are infinitely deep divots in spacetime itself. For the record, the latter is much harder to destroy.

Breaking free from seriousness is an opportunity for Chelsea and I to get hooked on the podcast.Cosmologists say there are benefits to thinking this way, too. wendy friedman at the University of Chicago. As more and more astronomical anomalies are observed that contradict the standard model of cosmology, it is becoming clear that our best empirical theory of the universe is due for revision. “As the data gets better and better and the theory gets more and more creative, something will start to fit,” Friedman says. “There are so many things we don’t understand, so we need crazy ideas right now.”

Nobel Prize-winning cosmologist Jim Peebles, one of the designers of the Standard Model, agrees that, when balanced, this kind of playful thinking is “an important part of science.” . “I indulge in blue-sky thinking. It’s a waste of time if you overdo it, a loss if you limit it,” he says.

Now, I don’t claim that Chelsea and I are trying to solve the problem of the Standard Model of cosmology by looking at ways to further arm the Milky Way. But I think something is lost when scientists take themselves too seriously. Admittedly, the conversations we had while making Dead Planets Society were a little silly, but they were also some of the most thought-provoking interactions I’ve ever had.

“When you cut the moon in half or blow up the sun or suddenly turn the Earth into a cube, well, all of this is interesting. It’s not just Dr. Evil or the Bond villains or the Borg,” Steves said. says. “This forces us to think about limit cases based on our current understanding of the science, and to have fun doing it. Both pushing and having fun are important.”

If we weren’t having fun, we would never have realized that if the sun went out, whales would outlive humans. This turns out to be true for most other types of apocalypse, so underwater life may have a better chance than terrestrial life in space. We would never have thought of using airgel as a kind of space fly strip to capture asteroids.

Steves quotes Rob Reiner’s cult film This is Spinal Tap, He describes it as a fount of scientific truth, saying, “There is a fine line between stupid and wise.” In other words, turning up stupidity to 11 doesn’t stop you from producing smart or interesting ideas.

The universe is big and messy, and it can sometimes feel like everything that can happen cosmically is probably happening somewhere else. That’s the beauty of it. Therefore, idle speculation, no matter how far-fetched, is not necessarily useless. It helps uncover the secrets of the universe, even if it means thinking like a cartoon villain or sometimes trying to kill the sun.

As for the bewilderment of his colleagues, let Steves respond: Are you a maniac, Leah? perhaps. But in the best possible way. ” I continue to carry this compliment with me as I continue to imagine exploring and sometimes destroying the universe.