Theoretical physicists have just figured out something that two of America’s most famous fictional scientists couldn’t: how to produce hypothetical subatomic particles called “axions” inside nuclear fusion reactors.
In the hit CBS sitcom “The Big Bang Theory”, the beloved character roommates Sheldon Cooper and Leonard Hofstadter worked intensely on this exact physics problem across three episodes of Season 5, but ultimately failed to crack it.
Now, Professor Jure Zupan from the University of Cincinnati, alongside co-authors from MIT, Fermi National Laboratory, and Technion–Israel Institute of Technology, have published a genuine solution in the Journal of High Energy Physics.
What are Axions and Why Do They Matter?
Axions are hypothetical particles that physicists suspect could finally explain Dark Matter. Although dark matter has never been observed directly, scientists believe it represents the vast majority of the mass in our universe, holding galaxies and stars together through its gravitational effects.
One of the leading theoretical possibilities is that dark matter is composed of these extremely light particles known as axions.
How Fusion Reactors Could Solve the Mystery
In their groundbreaking paper, Professor Zupan and his team analyzed a massive global fusion reactor currently being developed in the south of France. This reactor, powered by deuterium and tritium, is designed to generate energy, but researchers realized it will also create a massive flux of neutrons.
According to Zupan, these neutrons can generate dark sector particles (axions) in two distinct ways:
- Nuclear Reactions: High-energy neutrons smash into the lithium-lined walls of the reactor vessel, triggering reactions that create new particles.
- Bremsstrahlung (“Braking Radiation”): Neutrons bounce off other particles and slow down, releasing energy that can morph into axion-like particles.
Where Sheldon and Leonard Failed
This is exactly where the show’s fictional physicists hit a wall. “The general idea from our paper was discussed in ‘The Big Bang Theory’ years ago, but Sheldon and Leonard couldn’t make it work,” Zupan noted.
In one specific episode of the show, a whiteboard in the background features an equation describing how axions are generated by the sun. In a subsequent episode, a different equation appears on the board, but right below the calculations, a sad face is drawn in a different marker color.
Zupan explained that Sheldon and Leonard’s equations on the show compared the likelihood of detecting axions from a fusion reactor versus the sun. Because the sun is massive, the math showed it would always produce more particles than a reactor using the same solar processes—hence the sad face. However, the real-world physicists succeeded by utilizing a completely different set of nuclear processes that the fictional characters didn’t account for.
A Hidden Easter Egg for Real Scientists
The characters in the show never actually talk about axions or the whiteboards out loud; they were simply left as a hidden Easter egg for real-world scientists. “That’s why it’s fantastic to watch as a scientist,” says Zupan. “There are many layers to the jokes.”
With this discovery, real-world science has officially surpassed television fiction, opening up an entirely new path to discovering the universe’s most elusive mystery.
