As far as molecules go, beryllium hydride (BeH2) is minuscule - just two hydrogen atoms stuck to one beryllium atom. But, for now, it's a heavyweight champion: it's now the largest molecule ever modeled on a quantum computer, an emerging technology that could one day solve problems that plague ordinary computers. This advance, while still in the realm of what ordinary computers can do, could provide a powerful new way to discover new drugs and materials.
"I think it's very promising," says Marco De Vivo, a theoretical chemist at the Italian Institute of Technology in Genoa who studies how drugs interact with proteins. . "They are pushing the boundaries of today's computing."
Physicists and chemists often use computers to model the behavior of atoms and molecules. Such simulations require a lot of computing power, as interactions between three or more interacting particles quickly become extremely complex. Among other things, electrons inside molecules obey the strange laws of quantum mechanics - very small theories - which mean, for example, that it's impossible to determine the position and speed of an electron at the same time. This makes it more difficult to calculate the distribution of these electrons in the molecule. Even today's most powerful supercomputers can only simulate molecules of up to a few hundred atoms.
But scientists believe quantum computers are outperforming their classical Cousins. As early as 1981, Nobel laureate in physics Richard Feynman predicted that computers based on quantum mechanics could accurately simulate large molecules. Ordinary computers use bits that can be set to 0 or 1, while quantum computers use "qubits" that can be set to 0, 1 or both. These qubits can then be linked together to create a powerful quantum processor that, in theory, should be able to simulate molecules more efficiently than conventional computers. Many scientists believe that uncovering new drugs and materials will be the first killer application of future quantum computers, which universities and companies around the world are feverishly developing.
