Jan Guichelaar – författare

Founded in 1961 and still thriving today, the recreational magazine Pythagoras has given generations of high school students in the Netherlands a perspective on many branches of mathematics that are not taught in schools. This book is a selection of the best and most inspiring articles from Pythagoras magazine. It contains a mix of problems - some easy, some challenging, always original - as well as playful introductions to subjects in algebra, geometry, topology, number theory, and more. Concepts like sudoku and the magic square are given a whole new dimension. Articles on Escher's 'impossible objects', a recurring subject over the years, are part of a special section on mathematics and art. Smart high school students and anyone else with a sharp and inquisitive mind will find in this book a treasure trove rich enough to keep one's mind engaged for many weeks and months.

This is a thorough, very readable and excellently illustrated biography of Willem de Sitter (1872-1934), one of the most influential astronomers of his time, and also a co-author and correspondent of Einstein. Authored by a physicist and skilled writer, the book gives a beautiful and accessible description of the physics debated by Einstein and de Sitter, as well as the latter's alternative cosmological model, later known as the De Sitter Universe. But this is just part of a fascinating and varied life story involving numerous contributions to astronomy, as well as many places and personalities of early 20th century physics. The book will appeal to all those interested in astronomy and physics and their history.

This is a thorough, very readable and excellently illustrated biography of Willem de Sitter (1872-1934), one of the most influential astronomers of his time, and also a co-author and correspondent of Einstein. Authored by a physicist and skilled writer, the book gives a beautiful and accessible description of the physics debated by Einstein and de Sitter, as well as the latter's alternative cosmological model, later known as the De Sitter Universe. But this is just part of a fascinating and varied life story involving numerous contributions to astronomy, as well as many places and personalities of early 20th century physics. The book will appeal to all those interested in astronomy and physics and their history.