This puzzle comes from mathematical physicist John Baez. That’s John, not Joan (she is not a mathematical physicist, as far as I know), though they are in fact first cousins. You don’t normally expect that a physicist with a Ph.D…. Read More ›

This puzzle comes from mathematical physicist John Baez. That’s John, not Joan (she is not a mathematical physicist, as far as I know), though they are in fact first cousins. You don’t normally expect that a physicist with a Ph.D…. Read More ›