Template:Are You Sure/March 28

• ... that mathematician Alexander Grothendieck was the leading figure in the creation of modern algebraic geometry, and that his research extended the scope of the field and added elements of commutative algebra, homological algebra, sheaf theory and category theory, while his relative perspective led to revolutionary advances in many areas of pure mathematics?

• ... that the magnetic action on steel needles by ultraviolet light was used to detect and prevent crimes against light during the mid-1800s?