The 29-year-old Kastoryano, who is from Switzerland, has been a postdoctoral researcher at Freie Universität, working in the group headed by Professor Jens Eisert, since the start of this year. In June, he was granted a prestigious Alexander von Humboldt fellowship. Kastoryano is convinced of one thing: “With a new logic, we can build computers that are much faster than current models.”
A new logic for computers – what that means is instead of having conventional bits appear only with a value of 0 or 1, as previously, the bits of the future, dubbed “quantum bits,” can take on both conditions simultaneously, including everything in between. Or, to put it more poetically: If, in the digital model, an apple had to decide whether the stem would point upward or downward, the quantum mechanical model would have that apple with the stem pointing both up and down – and in every possible position in between. All at once. Hard to imagine? Kastoryano understands. “When you try to describe it in words, it sounds a bit esoteric, but within mathematics, it’s precise and clear,” he says.
Kastoryano speaks with a charming accent. His native language is French, and he grew up in the French-speaking western region of Switzerland. He earned a degree in physics and mathematics at Yale University before going on to doctoral studies at the University of Copenhagen. The start of this year brought him to Berlin. “When it comes to quantum physics, Germany is one of the most appealing research locations,” Kastoryano says.
One thing about Kastoryano’s research might seem surprising for someone who is doing research on future computer technology. His workplace is not a lab, and he doesn’t observe experiments. Instead, he sits at a desk in an office, with a pencil in his hand and a piece of paper in front of him. Behind him is a small chalkboard where he solves mathematical formulas. The only other working equipment he needs is his own head, Kastoryano says – and the ideas of others before him.
Once Kastoryano has read the latest essays on theories in quantum information science, he continues to think about those ideas. He jots down formulas on paper while mentally constructing a system that can be used to transmit information quickly and without disruptions. It is a purely mental structure, and one no one will ever see. “Most people have the wrong idea about physics,” the researcher says. “In school, it is explained to them using plastic examples. But it’s actually all about the fundamental laws of nature.” Nature – in Kastoryano’s case, that means an infinite collection of quantum bits: too small to be seen with the eye, but large enough to devote a lifetime of research to them.