To remove the contents of an egg without puncturing its shell or to drink the liquor in a bottle without removing the cork is clearly unthinkable or is it? Understanding the world of Einstein and curved space requires a logical conception of the fourth dimension.
This readable, informative volume provides an excellent introduction to that world, with 22 essays that employ a minimum of mathematics. Originally written for a contest sponsored by "Scientific American, "these essays are so well reasoned and lucidly written that they were judged to merit publication in book form. Their easily...