In the coming decades, the great American political debates will be less and less likely to feature Franklin Roosevelt-style Democrats squaring off against Ronald Reagan-style Republicans. Although ...

Researchers have developed an efficient way to characterize the effective many-body Hamiltonian of the solid-state spin system associated with a nitrogen-vacancy (NV) centre in diamond. The technique ...

No, not that Hamilton. I meant William Rowan Hamilton, the nineteenth century Irish mathematician. And not that sort of grid. I meant a square grid, like a chessboard or a Sudoku. Today’s two puzzles ...

This maze of jagged curls looks like something out of the world’s hardest puzzle book. How fast do you think you can solve it? Stuck? Don’t worry. It’s actually more of a connect the dots puzzle. The ...

Earlier today I set you two puzzles based on Hamiltonian paths in a square grid. A Hamiltonian path is one which visits every cell exactly once. (If you want a print out of the puzzles, click here.) 1 ...