Towards quantum chemistry on a quantum computer.

Exact first-principles calculations of molecular properties are currently intractable because their computational cost grows exponentially with both the number of atoms and basis set size. A solution is to move to a radically different model of computing by building a quantum computer, which is a device that uses quantum systems themselves to store and process data. Here we report the application of the latest photonic quantum computer technology to calculate properties of the smallest molecular system: the hydrogen molecule in a minimal basis. We calculate the complete energy spectrum to 20 bits of precision and discuss how the technique can be expanded to solve large-scale chemical problems that lie beyond the reach of modern supercomputers. These results represent an early practical step toward a powerful tool with a broad range of quantum-chemical applications.

Conservative management of renal carbuncles in children.

Renal carbuncles have traditionally been treated with surgical drainage and appropriate antibiotic therapy. Recently, 2 pediatric patients with well-documented renal carbuncles were treated with antibiotic therapy alone. Close follow-up documented complete resolution in both cases. Late studies showed no evidence of renal scarring or functional compromise.