UB physicists have upgraded the truncated Wigner approximation, allowing complex quantum simulations to run on laptops instead of supercomputers — making quantum research faster, cheaper, and more accessible.
Physicists at the University at Buffalo (UB) have made a major breakthrough that could transform how scientists explore the quantum world. They’ve upgraded a mathematical shortcut called the truncated Wigner approximation (TWA), enabling complex quantum simulations to run efficiently on ordinary laptops — no supercomputer required.
Their new approach, published in PRX Quantum in September 2025, offers a low-cost, easy-to-use framework that simplifies dense quantum equations into a practical format. This development could accelerate research in quantum physics, materials science, and computing by putting powerful simulation tools into the hands of more researchers worldwide.
From Supercomputers to Simple Systems
Until now, understanding quantum systems — where particles can exist in countless possible states — required enormous computing power. Traditional quantum simulations scale exponentially with complexity, making them impossible to run on standard machines.
To overcome this, scientists often rely on semiclassical physics, which balances quantum and classical mechanics to simplify calculations. TWA, a semiclassical technique first introduced in the 1970s, has been used to approximate quantum behavior in idealized systems. But it struggled with “real-world” conditions, where particles interact with their surroundings and lose energy — a process known as dissipation.
UB physicist Jamir Marino, along with co-authors Hossein Hosseinabadi and Oksana Chelpanova, has now expanded TWA to handle these messy, dissipative systems. The team’s upgraded model captures the essential physics while keeping computations light enough for consumer-grade laptops.
Turning Dense Math Into an Easy Tool
One of the biggest barriers to using TWA was accessibility. Each time researchers tried to model a new quantum system, they had to re-derive pages of complex mathematics. Marino’s team eliminated this hurdle by creating a conversion table — a kind of translator — that turns quantum problems into solvable equations automatically.
“Physicists can learn the method in a day and start running real simulations by the third day,” explains Chelpanova, now a postdoctoral researcher at UB. This means scientists can now explore phenomena like quantum chaos or spin dynamics on a laptop instead of relying on expensive supercomputing time.
Saving Supercomputers for the Hardest Problems
While the method won’t replace full-scale quantum computing, it’s a powerful new tool for tackling mid-level problems that don’t need massive resources. “A lot of what appears complicated isn’t actually complicated,” Marino says. “Our goal is to reserve supercomputers and AI for the problems that truly demand them.”
The research was supported by the National Science Foundation, German Research Foundation, and the European Union, reflecting its global impact on the future of quantum research.