A fascinating exploration of the pentagon and its role in various cultures The pentagon and its close cousin, the pentagram, have inspired individuals for the last two and half millennia, from mathematicians and philosophers to artists and naturalists. Despite the pentagon’s wide-ranging history, no single book has explored the important role of this shape in various cultures, until now. Richly illustrated, Pentagons and Pentagrams offers a sweeping view of the five-sided polygon, revealing its intriguing geometric properties and its essential influence on a variety of fields. Traversing time, Eli Maor narrates vivid stories, both celebrated and unknown, about the pentagon and pentagram. He discusses the early Pythagoreans, who ascribed to the pentagon mythical attributes, adopted it as their emblem, and figured out its construction with a straightedge and compass. Maor looks at how a San Diego housewife uncovered four previously unknown types of pentagonal tilings, and how in 1982 a scientist’s discovery of fivefold symmetries in certain alloys caused an uproar in crystallography and led to a Nobel Prize. Maor also discusses the pentagon’s impact on many buildings, from medieval fortresses to the Pentagon in Washington, D.C. Eugen Jost’s superb illustrations provide sumptuous visual context, and the book’s puzzles and mazes offer fun challenges for readers, with solutions given in an appendix.
Eli Maor Libri






Beautiful Geometry
- 208pagine
- 8 ore di lettura
The combination of art and exposition was quite effective. The writing is accessible to most reasonably well-educated laypeople, and I imagine that many such people would derive considerable pleasure dipping into this attractive and interesting book.--Mark Hunacek, MAA Reviews
The author's passion for the subject matter captivates readers, guiding them through a vibrant and expansive exploration of the topic. The narrative is filled with engaging insights and a wealth of information, making it an enriching experience for those interested in the themes presented.
Trigonometric Delights
- 236pagine
- 9 ore di lettura
Trigonometry has always been the black sheep of mathematics. It has a reputation as a dry and difficult subject, a glorified form of geometry complicated by tedious computation. In this book, Eli Maor draws on his remarkable talents as a guide to the world of numbers to dispel that view. Rejecting the usual arid descriptions of sine, cosine, and their trigonometric relatives, he brings the subject to life in a compelling blend of history, biography, and mathematics. He presents both a survey of the main elements of trigonometry and a unique account of its vital contribution to science and social development. Woven together in a tapestry of entertaining stories, scientific curiosities, and educational insights, the book more than lives up to the title Trigonometric Delights. Maor, whose previous books have demystified the concept of infinity and the unusual number e, begins by examining the proto-trigonometry of the Egyptian pyramid builders. He shows how Greek astronomers developed the first true trigonometry. He traces the slow emergence of modern, analytical trigonometry, recounting its colorful origins in Renaissance Europe's quest for more accurate artillery, more precise clocks, and more pleasing musical instruments. Along the way, we see trigonometry at work in, for example, the struggle of the famous mapmaker Gerardus Mercator to represent the curved earth on a flat sheet of paper; we see how M. C. Escher used geometric progressions in his art; and we learn how the toy Spirograph uses epicycles and hypocycles. Maor also sketches the lives of some of the intriguing figures who have shaped four thousand years of trigonometric history. We meet, for instance, the Renaissance scholar Regiomontanus, who is rumored to have been poisoned for insulting a colleague, and Maria Agnesi, an eighteenth-century Italian genius who gave up mathematics to work with the poor--but not before she investigated a special curve that, due to mistranslation, bears the unfortunate name the witch of Agnesi. The book is richly illustrated, including rare prints from the author's own collection. Trigonometric Delights will change forever our view of a once dreaded subject.
Venus in Transit
- 218pagine
- 8 ore di lettura
The 2004 transit of Venus captivated both casual observers and dedicated astronomers, marking a rare celestial event not seen since 1882. While some chose to ignore the spectacle, others meticulously planned their viewing, drawn by its beauty and historical significance. The transit provided essential data for determining the astronomical unit, the average distance between Earth and the sun, making it a pivotal moment in both science and history.
The Pythagorean Theorem
- 280pagine
- 10 ore di lettura
Frontmatter --Contents --List of Color Plates --Preface --Prologue: Cambridge, England, 1993 --1. Mesopotamia, 1800 BCE --Sidebar 1: Did the Egyptians Know It? --2. Pythagoras --3. Euclid's Elements --Sidebar 2: The Pythagorean Theorem in Art, Poetry, and Prose --4. Archimedes --5. Translators and Commentators, 500-1500 CE --6. François Viète Makes History --7. From the Infinite to the Infinitesimal --Sidebar 3: A Remarkable Formula by Euler --8. 371 Proofs, and Then Some --Sidebar 4: The Folding Bag --Sidebar 5: Einstein Meets Pythagoras --Sidebar 6: A Most Unusual Proof --9. A Theme and Variations --Sidebar 7: A Pythagorean Curiosity --Sidebar 8: A Case of Overuse --10. Strange Coordinates --11. Notation, Notation, Notation --12. From Flat Space to Curved Spacetime --Sidebar 9: A Case of Misuse --13. Prelude to Relativity --14. From Bern to Berlin, 1905-1915 --Sidebar 10: Four Pythagorean Brainteasers --15. But Is It Universal? --16. Afterthoughts --Epilogue: Samos, 2005 --Appendixes --Chronology --Bibliography --Illustrations Credits --Index.
Music by the Numbers
- 176pagine
- 7 ore di lettura
A fascinating investigation of the relationship between math and music--what they have in common, how they differ, and how each has informed the other, from Pythagoras to Schoenberg, from violin strings to superstrings. A delightful examination of how math and culture interact.--Ian Stewart, author of Significant Figures
The interest earned on a bank account, the arrangement of seeds in a sunflower, and the shape of the Gateway Arch in St. Louis are all intimately connected with the mysterious number e. In this informal and engaging history, Eli Maor portrays the curious characters and the elegant mathematics that lie behind the number. Designed for a reader with only a modest background in mathematics, this biography of e brings out that number's central importance in mathematics and illuminates a golden era in the age of science.
The Craft Kingdom: DIY and Craft Projects for Kids and Adults
- 114pagine
- 4 ore di lettura
Crafting and making art is very individual. These moments are completely yours. Even if you don't have access to all of the materials, you can be creative and experiment. If you prefer to use one type of material over the other, or if you prefer glue over sewing, do so. The main purpose is to enjoy it and create your vision at every moment. There is no need for any special skills for the projects in this book. However, those who sell artwork and wish to obtain the maximum results should stick to the projects and supplies as written. With that being said, there is no right or wrong way to craft and to make art, it comes down to having fun and express yourself. This book contains 92 DIY, crafts and art projects. Under each category, you will find the required supply for each project and a tutorial. At the end of the book, you will find stencils that will help you trace shapes and silhouettes for the projects. This book is the ultimate guide to DIY and Craft projects, organized by subjects. Contains step-by-step photographs and detailed instructions, features - Colors, Nature Craft, Stamps, Washi Tape, Soap Making, Candle Making, Recycling Art, Repurposing, Accessories, Fabric and Textile, Buttons, Paper and Paper Napkins.
Hudba v číslech, čísla v hudbě
- 184pagine
- 7 ore di lettura
Eli Maor se ve své knize věnuje vztahům mezi matematikou a hudbou. Nejednou čtenáři osvětlí řadu překvapivých detailů, když zkoumá, jak lze uplatnit matematický aparát v hudbě i naopak. Věnuje se například matematickému popisu vztahů mezi jednotlivými tóny, systémům ladění a jejich historickému vývoji. Píše o snaze matematiků a fyziků přesně popsat pohyb struny, prostor věnuje i zkoumání vzniku a povahy zvuku a jeho přenosu. Jinou oblastí, kde se projevují matematické zákonitosti, jsou rytmické poměry v hudbě, ale ani u nich paralely mezi matematikou a hudbou nekonči. Autor jakožto znalec matematiky a milovník klasické hudby zná obě oblasti detailně a čtenáře dokáže svým zájmem nakazit; a dělá to s podmanivou lehkostí. Anotace 2: Pythagoras v experimentech s monochordem stanovil zákonitosti mezi délkou struny a hudebními intervaly. Tzv. přirozené ladění bylo postupem času nahrazeno laděním temperovaným. Rozdíl mezi nimi vysvětluje přítomná kniha, a současně ozřejmuje, že tónové poměry jsou dány jednoduchými matematickými zákonitostmi, které se neomezují jen na huddební oblast.

