A normal viscous fluid can be set in motion only by a difference in pressure: squeeze one end of a straw and the fluid inside will move instantly to a lower-pressure region. This means that the flow ...

Pens, pencils and a facility with numbers. Also helpful: earplugs, plushies, a water bottle, calming herbal oil and the occasional “wild bifurcation” (a.k.a. a wild guess). Competitors at the World ...

The appeal of sudoku has spread to the prokaryotic world. A strain of Escherichia coli bacteria can now solve the logic puzzles – with some help from a group of students at the University of Tokyo, ...

Daily puzzlers would be quick to tell you that sudoku, Wordle’s mathematical cousin, is not as easy as it looks. The small grid, found often next to a word scramble or comic strip in a print newspaper ...