March 31, 2025—Quantum researchers hatch a butterfly, a gut microbe might control sugar cravings, and neuroscientists map the origin of near-death experiences.
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A fractal pattern known as “Hofstadter’s butterfly.” Yazdani Group
Quantum Butterfly Spreads Its Wings
A team of scientists arranged two sheets of graphene on top of one another, applied a magnetic field and measured the energy spectrum of electrons zipping between the two sheets—a common experimental setting for studying the superconducting potential of graphene. But a small error in calculation led to the discovery of a curious fractal pattern in the electrons’ energy levels, known as “Hofstadter’s butterfly.” Predicted almost fifty years ago by computer scientist Douglas Hofstadter, the butterfly only emerges under very specific electromagnetic conditions, which the scientists achieved by accident.
Why this matters: This is the first time the butterfly has been observed experimentally in a real material. The butterfly is like a “fingerprint” for the material being studied, explains Michael Scheer, study co-author and graduate student at Princeton. The distinct settings under which the butterfly appears will be slightly different based on the physical properties of whichever material is being studied, in this case graphene. So the technique could prove useful for research in nanotechnology or condensed matter physics.
What the experts say: “There’s something very satisfying about us working on this problem 50 years after Hofstadter’s calculation,” says Nuckolls. “In Hofstadter’s original paper, he basically concludes that ‘what I’ve calculated and predicted is really awesome, but no one’s ever going to see it because the [conditions] are never going to be achieved.’ Yet 25 years after that, researchers started seeing the first evidence supporting his calculations.” —Gayoung Lee, news intern
Microbes that Control Cravings?
Researchers measured the levels of a particular protein called free fatty acid receptor four (FFAR4) in mice and people with and without diabetes. They found that those with diabetes had low levels of the protein. In mice, the lower FFAR4 levels were tied to a decreased abundance of a gut microbe called Bacteroides vulgatus.
Why this matters: The researchers found that, in mice, less FFAR4 correlated with a greater preference for a high-sugar diet. That’s where the gut microbe comes in: B. vulgatus produces a metabolite called pantothenate—better known as vitamin B5—which triggers production of the hormone GLP-1, which regulates appetite. So, less FFAR4 means less B. vulgatus, less pantothenate and less GLP-1.
What the experts say: The identification of pantothenate from B. vulgatus as a molecule that stimulates GLP-1 secretion and reduces sugar preference is “a major finding,” says Sergueï O. Fetissov, a physiologist at the University of Rouen Normandy in France. It could open up new treatments for type 2 diabetes.
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Graphene is a single-atom-thick layer of carbon atoms, and physicists seem to keep finding surprising things the material can do. It's strong, light and flexible. And not only can it conduct electricity at super high speed, but it's also a superconductor—allowing energy to flow without resistance. You won't necessarily see it with your own eyes, but graphene may soon be in nearly every electronic device you touch.
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